The Conservative Party is asking Canada's spy agency to investigate whether recent comments by Ottawa's former ambassador to China pose a threat to the upcoming fall election.

John McCallum, who was fired as ambassador in January amid mounting tensions between Canada and China, said in a recent interview he has warned former contacts in China's Foreign Affairs Ministry that any further "punishments" imposed on Canada's exports could trigger a change of government that would be unfavourable to Beijing.

"Anything that is more negative against Canada will help the Conservatives, [who] are much less friendly to China than the Liberals," McCallum was reported as telling the South China Morning Post. The story was published Wednesday.

In a letter to Canadian Security Intelligence Service director David Vigneault, Conservative Party deputy leader Lisa Raitt and its public safety critic Pierre Paul-Hus ask CSIS to investigate whether McCallum's "disturbing" comments pose a threat to the security of Canada.

"This advice was partisan in nature and encouraged the government of China to take specific actions in order to influence Canada's democratic process," they write.

"This is highly inappropriate, for a myriad of reasons, not the least of which is the fact the Government of China continues to arbitrarily detain two Canadians, Michael Kovrig and Michael Spavor, and has taken other hostile actions towards Canada."

The party told Radio-Canada the letter was sent today.

A spokesperson for CSIS confirmed it had received the letter.

"As you can expect, we do not publicly comment or confirm or deny the specifics of our investigations," said John Townsend.

The letter also asks that McCallum's activities be included as part of the regular briefings to the critical election incident protocol panel — the new team set up to sound the alarm if it sees evidence the October federal election is being undermined.

"Canadians expect that the upcoming election will be conducted in a free and fair manner, and that any and all incidents of foreign interference will be fully investigated, with action taken to prevent said interference," wrote Raitt and Paul-Hus.

"We believe Mr. McCallum's actions, as confirmed by his own public statements, deserve the utmost scrutiny of your agency."

Freeland distances herself from comments

McCallum's interview comes after China suspended imports of Canadian canola, pork and beef following the arrest of Huawei executive Meng Wanzhou in Vancouver in December at the behest of American officials.

"This problem will pass," McCallum was quoted as saying in the article. "It's important for Canadian business people not just to come to China but to come often … especially when the going is tough."

McCallum was fired from his ambassadorial post after suggesting publicly that Meng, daughter of the founder of the Chinese telecom giant, had a strong case to fight extradition to the U.S.

Following recent comments from John McCallum, Foreign Affairs Minister Chrystia Freeland says the former ambassador to China does not speak on the federal government's behalf. 0:48

He also said any deal to spare Meng from prosecution in the U.S. should include the release of Kovrig and Spavor.

Canadian Foreign Affairs Minister Chrystia Freeland also took exception to her former cabinet colleague's comments while speaking to reporters at an event in London on Thursday.

"Mr. McCallum does not speak in the name of the Canadian government," she said.

"I think it is inappropriate for any Canadian to be advising any foreign government in ways it ought or ought not to behave to secure any particular election outcome in Canada."

When asked about the letter during a stop in Edmonton today, Prime Minister Justin Trudeau pointed to Freeland's comments the night before.

"The foreign minister addressed yesterday the comments by Mr. McCallum," Trudeau said.

"We will be unflinching about that in our communications both public and private as a government, because that is the path to both defending Canada's interests and defending the Canadians that are unjustly held."