Prime Minister Justin Trudeau says any decision to expel Chinese diplomats over alleged attempts to threaten a Conservative MP is being made "very, very carefully."

Trudeau says his government needs to consider potential Chinese backlash and what that would mean for the safety of Canadians and the prosperity of the country.

"This is a serious and significant question," Trudeau said Sunday, speaking with reporters in London.

"This is a decision not to be taken lightly and the foreign minister is leaning into this very, very carefully."

Conservative MP Michael Chong discovered only last week after a report in the Globe and Mail that CSIS had information in 2021 that the Chinese government was looking at ways to intimidate him and his extended family in Hong Kong.

Chong had sponsored a motion in the House of Commons labelling Beijing's treatment of Uyghur Muslims in China a genocide.

Trudeau has said CSIS did not tell anyone outside the spy agency about the threats, but Chong has said he was told the national security adviser knew about the information.

Trudeau says CSIS now has a directive that any such information be elevated to the highest levels, even if it seems minor.

"Does that mean every potential threat will land on my desk? Not necessarily, but it will mean that ministers and top public servants need to be assessed on it and anything that is deemed to be credible, we will take the necessary action on," Trudeau said.

Decision on Chinese diplomats being made 'very, very carefully:' @JustinTrudeau. #CDNPoli #China

"There wasn't a directive on this before."

The revelation about Chong is the latest in a string of foreign interference attempts allegedly made by the Chinese government in Canada in recent years, including efforts to influence the results of the 2019 and 2021 federal elections.

All political parties have agreed any attempted interference did not affect the final outcome of those elections, but Trudeau has appointed a special rapporteur to dig into what has happened and how Canada has and should respond.

Former governor general David Johnston, who was appointed to that role, is to decide in about three weeks whether a public inquiry is necessary and report back on all his findings by the fall.

The Conservatives and NDP want to go right to a public inquiry.

China denies all of it, including the allegations that one of its Toronto-based diplomats tried to start an intimidation campaign against Chong and his family.

Foreign Affairs Minister Mélanie Joly has said she's assessing what China's retaliation would be if Canada expels a diplomat.

"We’re assessing the consequences that we’ll be facing in case of diplomatic expulsion, because there will be consequences," Joly warned Thursday.

When asked Sunday by reporters what that retaliation could look like, Trudeau said Beijing has detained Canadians for reasons widely seen as arbitrary, and has limited Canadian imports such as canola and pork during unrelated diplomatic disputes.

This report by The Canadian Press was first published May 7, 2023.

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