But others say that's a mischaracterization and it's just a case of one subcontractor finishing one job before another subcontractor was hired for another.
AFL president Gil McGowan said Thursday that more than 270 workers at the Husky Sunrise project near Fort McMurray have been told they are off the job.
McGowan said the staff were working for a Toronto-based firm under contract at the site, and the contract has now been handed to an Italian-based company that uses foreign workers.
"Barely six months ago, Minister Jason Kenney was trumpeting assurances that no Canadians would lose work because of the Temporary Foreign Worker program," said McGowan.
"The events at Husky Sunrise show that, if he wasn't lying outright, he was deeply naive to make that claim."
However, Husky Energy said the reduction in workers is due to the job being finished.
Mel Duvall of Husky said in an email to The Canadian Press that Saipem Canada is the general contractor for the construction site, and the original project construction work was awarded to one of their subcontractors, Black & McDonald.
Read More RelatedThe Ugly, Shady Side Of Foreign Workers Program In Alberta
"We have been in discussions with Black & McDonald and confirmed their original piece of work came to a successful conclusion and they are adjusting their workforce accordingly."
Duvall said there are about 2,600 construction workers on the Sunrise site working for some 100 contractors and subcontractors. More than 90 per cent of those workers are Canadian, Duvall said.
Husky's contractors have had to hire temporary foreign workers in some cases because there has been a shortage of skilled workers in Canada, Duvall said.
Even Christopher Smillie with the building trades department in the Canadian office of the AFL-CIO took issue with the AFL.
"Mr. McGowan's statements say those people were replaced or sent off the job — well, those members have all been dispatched to new work sites," Smillie said.
"So they're not unemployed or displaced by this process. So when a job is over, those members come back to our hiring halls and then we send them to other jobs across the country. Those members all went through that process last month."
Also on HuffPost