One expert thinks Canada may be just at the beginning of a months-long diplomatic spat with India, as allies await more information on accusations New Delhi played a role in the death of a Canadian citizen.

Roland Paris, who leads the University of Ottawa graduate school of international affairs, says the countries have issued contradicting statements, making it difficult to find common ground.

On Monday, Prime Minister Justin Trudeau announced Canadian intelligence services are investigating "a potential link" between India's government and the death of Sikh leader Hardeep Singh Nijjar in B.C.

India calls those claims "absurd and motivated," leading Trudeau to urge India to take the allegations seriously and co-operate with a police investigation.

Canada expelled a senior Indian diplomat Monday.

Then India expelled a Canadian envoy, arguing it was because of concerns Canada is harbouring extremists who want a separate country for Sikhs.

Paris says the diplomat chill between is just starting, and it's unclear whether those tensions will get better or worse as the investigation continues.

"We're at the early stages of this period of diplomatic tension between the two countries," he said in an interview.

"It will be difficult, now that the Indian government has so publicly dug in their heels and offered a categorical denial of these allegations."

Canada in 'early stages' of diplomatic tension with #India: former Trudeau adviser. #CDNPoli

Paris, a former foreign policy adviser to Trudeau, noted there have been reports that the government went public with the accusation after queries from media and rumours in diaspora communities.

He said the entire issue underscores the importance of addressing foreign interference writ large.

"It's important for Canada to work closely with its allies to resist these kinds of pressures," Paris said.

"But first and foremost, we need to be able to resist them here at home. It's a much more dangerous world that we're living in, and we cannot rely as extensively as we have in the past on our allies. We really need to make sure that we're protecting Canadians in this."

Conservative Leader Pierre Poilievre has called on Trudeau to share more information about the intelligence Ottawa has, and former Liberal foreign minister Marc Garneau similarly said the government ought to back up the claim with more detail.

Paris said it's unclear whether India will retaliate against Canada, such as by blocking trade or delaying visas, and it's possible Ottawa might take similar steps against India.

But he noted India and Canada typically think of themselves as friends, despite long-standing tensions over Sikh separatists.

"I don't anticipate a lot of movement unless more information comes to light," Paris said.

"It looks like they were really trying to work back channels and use behind-the-scenes diplomacy to produce results directly with the Indians, and with the help of close Canadian allies. That clearly didn't work in the end."

This report by The Canadian Press was first published Sept. 20, 2023.

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