The fate of the proposed Keystone XL pipeline, which has become a thorny issue in Canada-U.S. relations, could be holding up U.S. President Barack Obama's decision for the next U.S. envoy to Canada.

Obama may be holding off on a nomination because he doesn’t want to have the U.S. Senate "hold that candidate hostage," Colin Robertson, a former diplomat, now working as the vice-president of the Canadian Defence and Foreign Affairs Institute told CBC News.

While the nomination must be confirmed by the Senate, U.S. senators can place a hold on presidential nominations, a practice that can be used as a tactic to advance policy or political goals regardless of party lines.

Diplomat Richard Sanders will mend the gap and serve as the newest American representative to Canada until a new ambassador is confirmed, the U.S. Embassy in Ottawa announced last week.

Sanders, who arrived in Canada on July 22, will act as chargé d’affaires in the interim as a matter of due course, following the departure of outgoing U.S. ambassador David Jacobson, whose term ended on July 15.

According to Robertson, Jacobson’s own nomination was delayed when then Democrat Senator Chris Dodd put a hold on it because he was unhappy with another appointment.

In this case, it may very well be that Obama doesn’t want any U.S. senator to hold his next ambassador to Canada as leverage to force his hand on the controversial Keystone XL pipeline, Robertson said.

"This isn’t a slight against Canada, it’s U.S. politics."

Keystone XL the 'dominant issue'

CBC News reported in April that Obama had picked Bruce Heyman, a partner from the investment firm of Goldman Sachs in Chicago, for the Canadian post.

Heyman, one of Obama’s top fundraisers, was set to be vetted and nominated for the job, but four months later there is still no word on Obama’s nomination.

It’s possible Heyman backed out of the nomination of his own accord before the vetting process was complete, but even if Obama had made Heyman's nomination official, any hope that a new U.S. envoy could get the nod this summer evaporated last week when Congress headed into a five-week summer break pushing all confirmations to the fall.

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Former U.S. Ambassador to Canada David Jacobson, centre, with current Canadian Ambassador to the U.S., Gary Doer, right, speak with former U.S. Ambassador to Canada David Wilkins. The proposed Keystone XL pipeline has become 'the dominant issue' between Canada and the U.S., Wilkins told CBC News. (Jeff McIntosh/The Canadian Press)

A decision over the controversial pipeline could also come this fall.

Uncertainty over the fate of the pipeline project may be affecting other aspects of the Canada-U.S. relationship.

TransCanada's $7-billion proposed Keystone XL pipeline, which would carry Alberta’s crude south to refineries in Texas, is "the dominant issue" between the two countries right now, said a former U.S. ambassador to Canada.

In an interview with CBC News, David Wilkins, Jacobson's predecessor, said Keystone XL has "sort of sucked the air out of the room."

The former ambassador, appointed by George W. Bush, is now a partner at the U.S. firm of Nelson Mullins, where he chairs the public policy and international law practice group. Its primary focus is on representing businesses on both sides of the U.S.-Canadian border.

"It’s imperative the U.S. go ahead and make a decision on that."

Otherwise, "it’s tough to tackle other issues," Wilkins said.

Prime Minister Stephen Harper reiterated last Friday the Canadian government’s assertion that the proposed pipeline would boost employment "on both sides of the border."

Harper's comments came days after the U.S. president downplayed the number of jobs that might result from the building of the pipeline, citing vastly lower numbers than supplied by the U.S. State Department’s draft environmental analysis of Keystone XL.

Canada, eh?

Although Ottawa isn’t London or Paris, being appointed to serve in Canada does not appear to be a hard sell south of the border.

Gordon Giffin, who was appointed ambassador to Canada by president Bill Clinton, said that "to be U.S. ambassador to Canada is one of the premier opportunities any president can offer someone."

In this country much is made about Ottawa's reputation as a boring city, but in the U.S. a posting in Canada is "something that is sought and competed for," Giffin said in an interview with CBC News.

According to Wilkins, about one-third of American ambassadors are political appointments. "That is, they generally have a relationship with the president, they are not career foreign service officers."

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Prime Minister Stephen Harper continues to make the case in favour of the proposed Keystone XL pipeline, as U.S. President Barack Obama weighs whether it is in the best national interest of his country. (Adrian Wyld/The Canadian Press)

Perhaps it's not so surprising then, that Obama has consistently rewarded his top fundraisers with political appointments.

Whoever the next U.S. ambassador is, both Wilkins and Giffin agree it’s imperative that the next envoy have the ear of the president.

"Some of our ambassadors drink wine and hold cocktail parties for a living. In a Canada-U.S. dynamic, you have a full-time job. It’s not just a ceremonial position," Giffin said.

Wilkins, who is from South Carolina, conceded that our Canadian winters "would be the only hesitancy somebody from the south may have about coming to Canada."

Even Giffin, who grew up in Canada for 17 years before returning to the U.S., admitted "Ottawa was a little bit colder" than he expected.

The only way around that, Wilkins said, was to "embrace the weather, not the TV." Wilkins said part of the Canadian experience was to skate on the Rideau Canal, even if it was just once a year.

"I stumbled around and looked pretty awful, but I got off without ever getting hurt." If anything, it made for "good speech material," Wilkins joked.

The Republican from South Carolina said he became "very familiar with Canadian maple syrup" and did try poutine at least "one time."

Wilkins said the best thing he did was to visit Canada’s 13 provinces and territories during his first six months as ambassador, and he offered this simple advice to the next U.S. ambassador: "Get out from behind your desk, get out from the embassy."