07/12/2013 11:32 EDT | Updated 09/11/2013 05:12 EDT

Ice cream, laughs and VIPs mark farewell party for Jacobson at Doer's residence

WASHINGTON - David Jacobson officially ended his tenure as U.S. ambassador to Canada this week before a retirement bash at Gary Doer's house featuring American VIPs and Ben and Jerry's sundaes created specially for the ice cream devotee.

Jacobson attended the traditional flag ceremony at the U.S. State Department on Thursday, a week after he and his wife, Julie, held a final Fourth of July party at the envoy's residence in Ottawa before packing up to head home to Chicago. An assistant secretary of state presented Jacobson with an ambassadorial flag and thanked him for his service.

Jacobson and Doer, Canada's ambassador to the United States, have become close friends during their corresponding years in office.

Both started their stints in October 2009 and have worked together on the Keystone XL pipeline, the Beyond the Border initiatives and securing a presidential permit for a new Detroit-Windsor bridge. They also came together with New York Gov. Andrew Cuomo to help resolve a bitter dispute on the binational Peace Bridge Authority at the border crossing between Buffalo and Fort Erie, Ont.

Guests said both men made funny, heartfelt speeches at the dinner, which was hosted by the Canadian American Business Council.

"It was a fun, low-key night that really highlighted the friendship between both ambassadors — a friendship that is really quite remarkably similar to the Canada-U.S. relationship in a lot of ways," said Maryscott Greenwood, head of the CABC.

"There is a lot of affection and admiration there and also a willingness to tackle issues together with humour and understanding. They've truly been an amazing, productive team."

Those in attendance included Ron Kirk, the retired U.S. trade representative; Ray LaHood, outgoing transportation secretary; three former U.S. ambassadors to Canada; several Obama administration envoys who have just returned to the U.S.; and three senators — Democrats Amy Klobuchar, Claire McCaskill and Jeanne Shaheen.

Former U.S. ambassador Jim Blanchard got a big laugh when he jokingly congratulated Doer and Jacobson on their success on Keystone XL, the controversial TransCanada pipeline that has yet to win approval from the Obama administration.

Dessert was two sundaes created for Jacobson by the Vermont-based Ben and Jerry's ice cream giant, one of which was named "Time For Retire-Mint."

Greenwood recited a Top 10 list of rejected sundae names. They included "Tar Sands Toffee" and "Arctic Char Chip."