McGuinty, who shocked the public with his surprise resignation last Monday, has said his successor must decide when to bring back the legislature which he prorogued as he stepped down.
The Liberal party's executive council decided Sunday on a Jan. 25, 2013 leadership convention date.
The opposition parties — who have been infuriated with the prorogation — were quick to argue that the date created too long a wait for a new legislative session.
The Progressive Conservatives and NDP continued to call on McGuinty to reverse his decision to pull the plug on political proceedings. They say Queen's Park was prorogued so the government could avoid scrutiny over its decision to cancel two power stations.
NDP house leader Gilles Bisson said in a release that waiting until early next year to bring the legislature back is simply not in the best interests of Ontarians.
"People want MPPs back to work — this year not next. The McGuinty Liberals can't shut down the Legislature until 2013," Bisson said.
Tory MPP Lisa MacLeod said there's no reason a Liberal leadership race couldn't be held with the legislature sitting.
"It's disgraceful that they want to hold the assembly hostage this long," she said. "It's very clear that we could still be having the house in session while they have their leadership (contest)."
Liberal leadership candidates face a deadline of 5 p.m. on Nov. 23 to submit their leadership forms. They'll need at least 250 signatures from party members and must pay a $50,000 entrance fee, while campaign spending will be capped at $500,000.
One high profile potential leadership candidate bowed out of the contest Sunday.
Ontario Liberal party president Yasir Naqvi said it was a "very personal decision" not to run for the party leadership.
"As the father of five-month old Rafi, I had to think long and hard," he said in a statement. "First and foremost, I am Rafi’s dad, and being a father is my most important new job."
Speculation that Naqvi would run grew last week when he recused himself from a conference call on the leadership convention, but wouldn't confirm whether he intended to run for leader.
Naqvi said he'll continue to work for his constituents in Ottawa Centre and looks forward to helping run the leadership convention.
"Now is a pivotal time in our party, and it is important that we ensure the leadership race is transparent, fair and robust," he said.
"I know many of my colleagues are considering entering the race, and I wish them all the best of luck in their deliberations."
Ontario Housing Minister Kathleen Wynne and Health Minister Deb Matthews are considered to be likely contenders, along with Energy Minister Chris Bentley and Economic Development Minister Brad Duguid, among others. But all remain coy about whether they'll throw their hat in the ring.
John Wilkinson, the former environment and revenue minister who lost his seat in last year's election, has also been mentioned as a possible candidate, as have former ministers George Smitherman and Sandra Pupatello.
Finance Minister Dwight Duncan told The Canadian Press that he's seriously considering a leadership bid.
But he says it's a huge commitment at his age — and for the rest of his professional career — to either be premier or rebuild the minority Liberals if they lose the next election.
McGuinty has told his ministers that they have to step down from cabinet if they want to run.
Observers predict the leadership convention is likely to be followed by a throne speech, budget and another prorogation to allow for a general election.
McGuinty said he prorogued the legislature to allow time for his embattled government to negotiate with unions and the Progressive Conservatives on a public-sector wage freeze.
But it also brings all legislative business to a standstill and kills planned committee hearings into cancelled power plants in Oakville and Mississauga and a rare contempt motion against Bentley.
The opposition parties have repeatedly accused McGuinty of proroguing to avoid more bad publicity over the decision to cancel the gas plants, especially after a second batch of 20,000 documents was released after the premier and his ministers had insisted all relevant records had been released in September.
The second batch — following 36,000 documents released Sept. 24 to comply with a Speaker's order — came just three days before McGuinty announced that he'd step down as premier once a new leader was chosen.
The government said its decisions to cancel the power plants in Oakville and Mississauga will cost taxpayers $230 million, but the opposition parties say it's triple that figure or even higher.
— with files from Will Campbell.
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