Prime Minister Stephen Harper will be a no-show at the first question period of the new session of Parliament.

It was announced shortly after Wednesday's throne speech that Harper is off to Brussels on Thursday to wrap up a long-promised free-trade deal with the European Union.

But some may say the timing is convenient, as Harper faced a number of tough questions regarding the Senate expense scandal and the recent Elections Canada charges laid against his former parliamentary secretary, Dean Del Mastro.

And that has his main rivals accusing the prime minister of running scared.

NDP Leader Tom Mulcair, who won rave reviews for his direct, pointed questions in the House last spring, said Harper was showing "cowardly behaviour".

Mulcair told CBC's Evan Solomon that Harper's absence in the House of Commons will be both "undignified and unprecedented."

The NDP leader was also highly critical of Harper's decision to prorogue Parliament by one month this summer. NDP MPs instituted "virtual question periods" on Twitter, where they lobbed questions at Harper and his key ministers online, but were mostly met with radio silence.

"He can run, even to Brussels, but he can't hide," Mulcair said.

Liberal Leader Justin Trudeau also told Solomon he was disappointed, but vowed Liberals will hold Harper's feet to the fire this fall.

"I think we've gotten used to a prime minister that prefers not to be held accountable," Trudeau said.

This is not the first time Harper has hit the road in advance of a difficult question period.

In May, Harper took off to South America shortly after his chief of staff, Nigel Wright, resigned over the infamous $90,000 cheque he cut for then-Tory Senator Mike Duffy.

A "very upset" Harper addressed his caucus the morning before departing, but did not respond to questions yelled from reporters.

That left Foreign Affairs Minister John Baird to field the brunt of questions from rivals later that afternoon in the House.

"Mr. Speaker, when the going gets tough, the tough get going … to Peru, apparently," Mulcair said.

The EU deal could be a major feather in Harper's cap. One agriculture expert has said it could mean up to $1.3 billion in new exports from Canada, mostly beef.

And perhaps most importantly for Tories, it may give Harper another chance to change the channel.

NDP House Leader Nathan Cullen told HuffPost on Sunday that Harper is facing a grilling this fall over the various controversies that have plagued Tories all summer.

"Boy, oh boy, he's going to have trouble with question period," Cullen said. "If the prime minister didn't outright lie, then he lied by hiding the truth that he knew, and he needs to account for that."

With files From The Canadian Press

Also on HuffPost:

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  • Stephen Harper and wife Laureen in 2011. Source: <a href="http://www.flickr.com/photos/pmharper/8472663517/in/photostream" target="_blank">Flickr</a>

  • Whoops, How Did This Get In Here...

    Part of a painting of Prime Minister Stephen Harper fully nude, by Kingston artist Maggie Sutherland, is shown at the Central Kingston public library in Kingston, Ont. on May 18, 2012.

  • Beer Me!

    Prime Minister Stephen Harper gets behind the bar at the Victoria pub in Montreal Friday, March 16, 2012 where he stopped in to meet some supporters and have a drink for St. Patricks Day.

  • You Eat Half, And I'll Eat Half

    Conservative leader Stephen Harper and Laureen Harper stand next to a tray of hot cross buns at a bakery in Mississauga, on April 23, 2011.

  • Cuddle Time!

    Stephen Harper with wife Laureen and their chinchilla Charlie. Source: <a href="http://www.flickr.com/photos/pmharper/8425819048/in/photostream" target="_blank">Flickr</a>

  • Easy Rider

    Prime Minister Stephen Harper waves after going for an ATV ride as he visits a farm for a campaign event in Wainfleet Ont., on Monday, April 4, 2011.

  • Nom Nom Nom

    Prime Minister Stephen Harper eats maple taffy as he visits a sugar shack in Norbertville, Quebec on Tuesday, April 5, 2011.

  • Muahhh

    Prime Minister Stephen Harper gives his wife Laureen a kiss following a day of G-20 meetings in Toronto. June 27, 2010. Source: <a href="http://www.pm.gc.ca/eng/media_gallery.asp?media_category_id=938&media_category_typ_id=6#cont" target="_blank">Pm.gc.ca</a>

  • Can I Keep Them?

    Prime Minister Stephen Harper plays with foster kittens at 24 Sussex. May 1, 2010. Source: <a href="http://www.pm.gc.ca/eng/media_gallery.asp?media_category_id=900&media_category_typ_id=6&media_id=5512" target="_blank">Pm.gc.ca</a>

  • Incoming!

    Conservative Leader Stephen Harper throws a small snowball at photographers after talking with reporters at a campaign stop in Guelph, Ontario Saturday, Jan. 21, 2006.

  • Thank God You're Not Wearing Overalls

    Prime Minister Stephen Harper gives Taylor Swift the book "Maple Leaf Forever" before her concert at Scotiabank Place in Ottawa. May 20, 2010. Source: <a href="http://www.pm.gc.ca/eng/media_gallery.asp?media_category_id=900&media_category_typ_id=6&media_id=5512" target="_blank">Pm.gc.ca</a>

  • Wedding Crasher

    Stephen Harper <a href="http://www.huffingtonpost.ca/2012/10/23/harper-wedding-photos-ottawa_n_2006374.html" target="_blank">surprises an Ottawa couple on their wedding day</a> in 2012.

  • Yep, Definitely A Cat Person

    Laureen Harper laughs as she holds a husky dog with Canadian Prime Minister Stephen Harper as they tour Caribou Crossing, Yukon, south of Whitehorse Monday August 20, 2012.

  • Harper Road

    Stephen Harper, his children Ben and Rachel, and wife Laureen cross Abbey Road in 2009. Source: <a href="http://on.fb.me/12OfGXN" target="_blank">Facebook</a>

  • Bonjour, Bonhomme

    Prime Minister Stephen Harper hams it up with Bonhomme Carnaval in the Prime Minister's Centre Block Office. November 25, 2010. Source: <a href="http://www.pm.gc.ca/eng/media_gallery.asp?media_category_id=1238&media_category_typ_id=6#cont" target="_blank">Pm.gc.ca</a>

  • Trendsetter

    Canadian Prime Minister Stephen Harper, far left, watches a third round match between Agnieszka Radwanska, of Poland, and Serbia's Jelena Jankovic with his children Rachel, center, and Benjamin, right, at the 2012 US Open tennis tournament, Saturday, Sept. 1, 2012, in New York.

  • Psst! I Like Your Hat

    Catherine, Duchess of Cambridge, speaks with Canadian Prime Minister Stephen Harper during Canada Day celebrations on Parliament Hill in Ottawa on July 1, 2011.

  • Giggle Fit!

    Prime Minister Stephen Harper and his son Ben watch a bloopers show while attending the Calgary Flames NHL hockey game against the Edmonton Oilers in Calgary, Saturday, April 11, 2009.

  • In The Key Of C Major

    Prime Minister Stephen Harper practices a few chords after arriving at home from work. February 19, 2011. Source: <a href="http://www.pm.gc.ca/eng/media_gallery.asp?media_category_id=1457&media_category_typ_id=6#cont" target="_blank">Pm.gc.ca</a>

  • Love You, Mom

    Conservative leader Stephen Harper gets a hug from his mother Margaret during a visit to his campaign office in Calgary, Saturday May 29, 2004.

  • We Can't All Grow A Pirate 'Stache Like Trudeau

    Prime Minister Stephen Harper holds up a moustache scarf to kick off the start of ‘Movember’, November 1, 2012 Source: <a href="http://www.flickr.com/photos/pmharper/8146161138/in/photostream" target="_blank">Flickr</a>

  • The Sweet Side Of Politics

    Senior Legislative Assistant, Katherine Locke, left, and Government House Leader Special Assistant, Zoe Lawson, show off their House of Commons gingerbread house to Prime Minister Stephen Harper in his office on Dec. 16, 2010. The gingerbread house was filled with rows of gummi bears as members of Parliament. Source: <a href="http://www.pm.gc.ca/eng/media_gallery.asp?media_category_id=1355&media_category_typ_id=6#cont" target="_blank">Pm.gc.ca</a>

  • Beach Boy

    Prime Minister Stephen Harper waves to tourists as he walks on the beach after the closing of the VI Summit of the Americas on April 15, 2012 in Cartagena de Indias, Colombia.

  • Game Face

    Prime Minister Stephen Harper plays a game of table tennis with Team Canada's Mo Zhang at Canada House in London on Tuesday, June 5, 2012.

  • Whaddya Mean It Doesn't Fit?

    Prime Minister Stephen Harper tries on an old hockey helmet at he tours the Yukon's Hockey History exhibit at the McBride Museum in Whitehorse, Yukon on Thursday, August 25, 2011.

  • Goooaaaaallll!

    Stephen Harper, his son Ben, and Wayne Gretzky watch the men's ice hockey team's gold medal game at the 2010 Winter Olympics in Vancouver. Source: <a href="http://www.flickr.com/photos/pmharper/8457917081/in/photostream" target="_blank">Flickr</a>

  • Who Said Politics Can't Be Fun?

    Stephen Harper and his son Ben hit balloons into the crowd after his speech at the party's three-day policy convention in Montreal on Friday March 18, 2005.

  • Jam Sesh

    Prime Minister Stephen Harper and Jamie Robinson (guitar) play along with Blue Rodeo's front man Jim Cuddy, and recording artist Jimmy Rankin as they belt out a tune during a Juno Awards reception at 24, Sussex March 31, 2012. Source: <a href="http://www.pm.gc.ca/eng/media_gallery.asp?media_category_id=2099&media_category_typ_id=6#cont" target="_blank">Pm.gc.ca</a>

  • Party Politics

    Prime Minister Stephen Harper, looks up from dishing out pancakes at Stampede breakfast in Calgary, Alta., Sunday, July 10, 2011.

  • I Spy Something Cute

    Stephen Harper welcomes two Chinese pandas at Toronto's Pearson Airport on March 25, 2013. Source: <a href="http://www.flickr.com/photos/pmharper/8588948719/in/photostream" target="_blank">Flickr</a>

  • Flashback

    A young Stephen Harper.

  • Just Smile And Back Away Slowly

    Clowns ham it up with Prime Minister Stephen Harper at the IAAF World Junior Championships in Moncton, New Brunswick. July 19, 2010. Source: <a href="http://www.pm.gc.ca/eng/media_gallery.asp?media_category_id=1037&media_category_typ_id=6#cont" target="_blank">Pm.gc.ca</a>

  • Hats Off

    Prime Minister Stephen Harper, left, throws Senator Gerry St. Germain's cowboy hat into the crowd after presenting him with a new one as his wife Margaret St. Germain, right, laughs during a barbecue at St. Germain's ranch in Surrey, B.C., on Monday August 6, 2012.

  • Thumbs Up, Up And Away

    Prime Minister Stephen Harper gives the thumbs up from the cockpit of his campaign plane as he arrives in Ottawa,Tuesday May 3, 2011.

  • He's A Belieber

    Stephen Harper presents Justin Bieber with a Diamond Jubilee Medal on Nov. 23, 2012. Source: <a href="http://www.flickr.com/photos/pmharper/8212520594/in/photostream" target="_blank">Flickr</a>

  • I'm With Him

    Stephen Harper and Wayne Gretzky, joined by students on an outdoor ice rink in Saskatoon on Feb. 5, 2010. Source: <a href="http://on.fb.me/ZTlKy6" target="_blank"> Facebook</a>

  • Shhh... This Is The Best Part

    Stephen Harper, wife Laureen and Suraksha, Grade 10, visit an IMAX theatre in Bangalore, India on Nov. 8, 2012.

  • Umm... This Is My Costume

    Prime Minister Stephen Harper poses for a photograph with Halloween trick-or-treaters at his official residence in Ottawa, Wednesday, October 31, 2012.

  • Is It Cold, Or Is It Just Me?

    Prime Minister Stephen Harper bundles up in a parka as he tours Frobisher Bay in Iqaluit, Nunavut on Thursday, February 23, 2012.

  • One Of Harper's Many Hats

    Canada's Prime Minister Stephen Harper adjusts his hat prior to the arrival of Britain's Prince William and his wife Catherine, Duchess of Cambridge, for the official start of the Calgary Stampede parade in Calgary, Alberta, July 8, 2011.

  • D'awww

    Prime Minister Stephen Harper and his wife Laureen play with some furry friends at the official opening of the new Ottawa Humane Society facility on July 6, 2011. Source: <a href="http://www.pm.gc.ca/eng/media_gallery.asp?media_category_id=1724&media_category_typ_id=6#cont" target="_blank">Pm.gc.ca</a>

  • Omigod, So Cute

    Met Batisse X, official mascot of the Royal 22nd Regiment, prior to welcoming French PM Jean-Marc Ayrault to Ottawa. Source: <a href="http://www.flickr.com/photos/pmharper/8554783327/in/photostream" target="_blank">Flickr</a>

  • I Can Totally Take You

    Prime Minister Stephen Harper receives a cricket lesson from Ankur Biswas, cricket team captain, at the Bishop Cotton Boys School. Source: <a href="http://on.fb.me/12OffwT" target="_blank">Facebook</a>

  • Mush!

    Prime Minister Stephen Harper drives a dog sled after meeting mushing teams at the Arctic Winter Games in Yellowknife, N.W.T., Monday, March 10, 2008.

  • A Very Harper Holiday

  • Hanging With The Golden Girls

    Stephen Harper meets Canada's women's hockey team, gold medal winners at the 2010 Winter Olympics in Vancouver. Source: <a href="http://on.fb.me/17v6qKa" target="_blank">Facebook</a>

  • Tough Cookie

    Prime Minister Stephen Harper and his wife Laureen, left, make cookies with 10-year-old brain cancer survivor Baxton Wacholtz, right, and his mom Michelle, of Telkwa, B.C., during a photo opportunity at Ronald McDonald House in Vancouver, B.C., on Tuesday August 7, 2012.

  • Does This Mean I'm In The Band?

    Canadian musician Jens Lindemann visits Stephen Harper before a concert. "His blue trumpet reminded me of Sgt. Pepper," according to Harper. Source: <a href="http://www.flickr.com/photos/pmharper/8519328992/in/photostream" target="_blank">Flickr</a>

  • Stanley's Not Going To Be Happy About This

    Met with Constable Dan Allen of the Child at Risk Response Team (and Cagney the dog) while in Calgary. Source: <a href="http://www.flickr.com/photos/pmharper/8640427193/in/photostream" target="_blank">Flickr</a>

  • Say, 'Happy Halloween!'

    Prime Minister Stephen Harper points out the camera to baby Grayson, dressed up as a giraffe, during his first time trick-or-treating at 24 Sussex. Source: <a href="http://on.fb.me/10ppG5w" target="_blank">Facebook</a>

  • Bear Hug

    Stephen Harper hugs his daughter Rachel Hugging Rachel as results come in after the 2011 election. Source: <a href="http://on.fb.me/15WI2TY" target="_blank">Facebook</a>