OTTAWA -- Employment Minister Jason Kenney says there's been a significant decrease in applications for temporary foreign workers since the government announced an overhaul of the troubled program earlier this year.

"We announced a fundamental suite of reforms to the temporary foreign worker program earlier this year to ensure that it is used only as a last and limited resort, and that Canadians always come first in the workforce," he said in response to queries from the opposition during the Commons question period on Tuesday.

"Since those reforms were announced we have seen a 75 per cent reduction in the number of applications for temporary foreign workers on the part of employers."

Kenney's department says that the number of applications received in July and August was about 74 per cent lower than during the same time period in 2012, before the crackdown.

New rules introduced in June aim to make it more difficult for employers to hire temporary foreign workers, requiring them to meet strict criteria to ensure Canadians are first in line for jobs.

It also makes the process much more costly. For 40 years, the program was available to businesses across Canada with no annual assessment fee.

A year ago, the Conservatives implemented a $275 fee. In June, that fee was hiked to $1,000 for each worker, an expense that essentially placed the temporary foreign worker program out of reach for many small businesses.

Some employers have complained that the new rules are too onerous and make it difficult for them to operate in areas of the country with low unemployment.

Western premiers have also raised concerns about the overhaul, saying their provinces have a pressing need for skilled labour.

Jinny Sims, the NDP's employment and immigration critic, mocked Kenney's defence of the overhaul, pointing to the case of 58 electricians in Saskatchewan who said they were laid off from Alliance Energy in May while the company's temporary foreign workers were kept on.

"The rule of asking employers if they think a Canadian will lose his or her job 'now or in the foreseeable future' gives huge wiggle room to employers," Sims said. "When will the government make real changes and have real penalties?"

Kenney told Sims to bring those allegations to Service Canada "or to the Canada Border Services Agency so that a formal inquiry can be launched."

The federal government, however, is already investigating the company, which says it was in full compliance of the rules of the temporary foreign worker program.