India on Tuesday described as "absurd" and "motivated" Canadian Prime Minister Justin Trudeau's allegation that New Delhi was involved in any act of violence in Canada.

India's reaction came after Canada expelled a senior Indian diplomat with Canadian Prime Minister Justin Trudeau alleging that the Indian government may have had links to the assassination of Sikh leader Hardeep Singh Nijjar in that country.

"Allegations of Government of India's involvement in any act of violence in Canada are absurd and motivated," the Ministry of External Affairs said.

"Similar allegations were made by the Canadian Prime Minister to our Prime Minister, and were completely rejected," it said.

"We are a democratic polity with a strong commitment to rule of law," the MEA said.

It said such "unsubstantiated" allegations seek to shift the focus from Khalistani terrorists and extremists, who have been provided "shelter in Canada and continue to threaten India's sovereignty and territorial integrity".

"The inaction of the Canadian Government on this matter has been a long-standing and continuing concern," it said. 

Canada expels Indian diplomat

 Canada expelled a top Indian diplomat Monday as it investigates what Prime Minister Justin Trudeau called credible allegations against India's government.

Trudeau said in Parliament that Canadian intelligence agencies have been looking into the allegations after Sikh leader Hardeep Singh Nijjar, a strong supporter of an independent Sikh homeland known as Khalistan, was gunned down on June 18 outside a Sikh cultural centre in Surrey, British Columbia.

Trudeau told Parliament that he brought up the slaying with Indian Prime Minister Narendra Modi at the G-20 last week. He said he told Modi that any Indian government involvement would be unacceptable and that he asked for cooperation in the investigation.

Canadian Foreign Minister Mlanie Joly said the head of Indian intelligence in Canada has been expelled as a consequence.

"If proven true this would be a great violation of our sovereignty and of the most basic rule of how countries deal with each other," Joly said. "As a consequence we have expelled a top Indian diplomat."

The Indian Embassy in Ottawa did not immediately answer phone calls from The Associated Press seeking comment.

The expulsion comes as relations between Canada and India are tense. Trade talks have been derailed and Canada just cancelled a trade mission to India that was planned for the fall.

At the G-20 meeting, Modi expressed "strong concerns" over Canada's handling of the Punjabi independence movement among the overseas during a meeting with Trudeau at the G-20, according to a statement released by India's Ministry of External Affairs.

The statement described the Sikh movement as "promoting secessionism and inciting violence" against Indian diplomats. It called on Canada to work with India on what New Delhi said is a threat to the Canadian Indian diaspora.

Canada has a Sikh population of more than 770,000, or about 2 per cent of its total population.

"Over the past number of weeks Canadian security agencies have been actively pursuing credible allegations of a potential link between agents of the government of India and the killing of a Canadian citizen, Hardeep Singh Nijjar," Trudeau said.

Trudeau said Canada has declared its deep concerns to the Indian government. "Any involvement of a foreign government in the killing of a Canadian citizen on Canadian soil is an unacceptable violation of our sovereignty.

Trudeau said his government has been working closely and coordinating with Canada's allies on the case.

"In the strongest possible terms I continue to urge the government of India to cooperate with Canada to get to the bottom of this matter," he said.

Trudeau said he knows there are some members of the Indo-Canadian community who feel angry or frightened, and he called for calm.

Public Safety Minister Dominic LeBlanc said Canada's national security adviser and the head of Canada's spy service have travelled to India to meet their counterparts and to confront the Indian intelligence agencies with the allegations.

He called it an active homicide investigation led by the Royal Canadian Mounted Police.

Joly said Trudeau also raised the matter with US President Joe Biden and UK Prime Minister Rishi Sunak. Joly also said she would raise the issue with her peers in the G7 on Monday evening in New York City ahead of the United Nations General Assembly.

Opposition Conservative leader Pierre Poilievre said if the allegations are true they represent "an outrageous affront to our sovereignty."

Opposition New Democrat leader Jagmeet Singh, who is himself Sikh, called it outrageous and shocking. Singh said he grew up hearing stories that challenging India's record on human rights might prevent you from getting a visa to travel there.

"But to hear the prime minister of Canada corroborate a potential link between a murder of a Canadian citizen on Canadian soil by a foreign government is something I could never have imagined," Singh said.

Khalistan movement

The Khalistan movement is banned in India, where officials see it and affiliated groups as a national security threat. But the movement still has some support in northern India, as well as beyond, in countries like Canada and the United Kingdom which are home to a sizable Sikh diaspora.

Nijjar was organizing an unofficial referendum in India for an independent Sikh state at the time of this death. Indian authorities announced a cash reward last year for information leading to Nijjar's arrest, accusing him of involvement in an alleged attack on a Hindu priest in India.

The World Sikh Organization of Canada called Nijjar an outspoken supporter of Khalistan who "often led peaceful protests against the violation of human rights actively taking place in India and in support of Khalistan."

Niijar's New York-based lawyer, Gurpatwant Singh Pannun, has said Niijar was warned by Canadian intelligence officials about being targeted for assassination by "mercenaries" before he was gunned down.

(With inputs from PTI, AP)