Amidst the diplomatic strain in India-Canada relations, India's envoy here has warned that the Sikh separatist groups in Canada were crossing "a big red line" that New Delhi sees as a matter of national security and of the country's territorial integrity.

Indian High Commissioner to Canada Sanjay Kumar Verma said this on Tuesday in his first public remarks since three Indian nationals accused of killing Khalistan separatist Hardeep Singh Nijjar last year were arrested and produced before a court by Canadian police.

Verma seemed to link the case to domestic crime, CTV News reported.

He also warned that Sikh groups in Canada who call for the separation of their homeland from India are crossing "a big red line" that New Delhi sees as a matter of national security.

"Indians will decide the fate of India, not the foreigners," Verma told the Montreal Council on Foreign Relations, a prominent think-tank.

He also told the Council that relations between India and Canada are positive overall despite "a lot of noise".

Verma also said that the two countries are "trying to resolve this issue." "We are ready to sit down at the table any day, and we are doing that," he said.

Verma said the deeper problems underneath the recent "negative" developments have to do with Canada's misunderstanding of "decades-old issues," which he blames Canadians of Indian origin for resurfacing.

He said his chief concern is "national-security threats emanating from the land of Canada," noting that India does not recognise dual nationality, so anyone who emigrates is considered a foreigner.

"Foreigners having, if I can call it, (an) evil eye on the territorial integrity of India — that is a big red line for us," he said.

He did not specify whether he was referring to foreigners being involved in the Nijjar case or the issue of Sikh separatism more broadly, the report said.

On Tuesday, India told Canada that celebration and glorification of violence should not be a part of any civilised society. Democratic countries which respect the rule of law should not allow intimidation by radical elements in the name of freedom of expression.

"We continue to remain concerned about the security of our diplomatic representatives in Canada and expect the Government of Canada to ensure that they are able to carry out their responsibilities without fear," the Ministry of External Affairs said in a statement in response to the violent imagery being used by extremist elements in Canada against India's political leadership.

"We again call upon the Government of Canada to stop providing criminal and secessionist elements a safe haven and political space in Canada,” the MEA spokesperson said in New Delhi.

Earlier on Tuesday, Canadian Foreign Minister Melanie Joly stood by allegations that the Indian government was complicit in the slaying of Nijjar last year.

Nijjar, a Canadian citizen, was shot dead outside a gurdwara in Surrey on June 18, 2023.

The killing sparked a wave of protests, with some Sikh groups circulating posters that threatened Indian diplomats in Canada by name.

Joly said her goal is still to conduct diplomacy with India in private.

She said she would let the police investigate instead of providing any new commentary on the case.

"We stand by the allegations that a Canadian was killed on Canadian soil by Indian agents," Joly said on Parliament Hill.

"The investigation by the RCMP is being done. I won’t further comment and no other officials from our government will further comment," she said, referring to the ongoing probe by the Royal Canadian Mounted Police.

Meanwhile, Verma also mentioned "so many positive things" happening in the relationship between India and Canada.

He noted the annual value of two-way trade is 26 billion Canadian dollars, and in the past 11 months, there has been a 75 per cent jump in Canadian lentil exports and a 21 per cent increase in Indian-prepared medicines reaching Canada.

On Tuesday, the group Sikhs for Justice called for Verma's speech to be cancelled, citing the Nijjar case and allegations of foreign interference by India.

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