NEW YORK: Prime Minister Justin Trudeau urged India Thursday to cooperate in the murder investigation to reach the bottom of the truth, after accusing India of killing a Sikh separatist on Canadian soil which sparked a diplomatic row between the two countries. 

Both countries were locked in a diplomatic standoff when Canada's leader while in a speech in the House of Commons said that he had credible intelligence about the Indian involvement in murdering Hardeep Singh Nijjar. 

"We call upon the government of India to work with us to establish processes to uncover the truth of this matter and to allow for justice and accountability to be served," Trudeau said on the sidelines of the United Nations General Assembly in New York.

The 51-year-old did not release the information to corroborate his allegations that led him Monday to name India as a perpetrator behind the killing suggesting that would be left for courts to make public should the case ever go to trial.

Trudeau said Monday that Indian agents played a role in the June murder of Hardeep Singh Nijjar, a Canadian citizen, near Vancouver.

The fallout prompted tit-for-tat diplomatic expulsions and a forceful denial from India, which said any suggestion it played a role in Nijjar's killing was "absurd."

India also stopped handling visa applications in Canada, blaming "security threats" which they said were "disrupting" the work of their officials and sought a reduction of Canadian diplomatic staff in India.

Trudeau insisted Thursday that his government "is not looking to provoke or cause problems" when asked why Canada's allies' reactions to the allegations appeared muted.

Western powers led by the United States have been courting India for years, seeing a natural ally in the billion-plus democracy as concerns mount about China.

"There is no question that India is a country of growing importance and a country that we need to continue to work with," Trudeau said.

"But we are unequivocal around the importance of the rule of law and unequivocal about the importance of protecting Canadians."

Trudeau requested the Indian government's help, saying he merely wanted to ensure the safety of Canadians. "We demand that the Indian government take this issue seriously and ensure that justice is served in this case. I'm going to keep working to keep Canadians secure."

He also said to have discussed his concerns with PM Modi in a "direct and frank" chat.

"We have an independent justice system and robust processes that will follow its course and we call upon the government of India to engage with us to move forward on getting to the truth of this matter," Trudeau had added.