India has suspended new visas for Canadians and asked Ottawa to reduce its diplomatic presence in the country, sharply escalating a spat triggered by Prime Minister Justin Trudeau's accusations linking New Delhi to a Sikh separatist's murder.
India was willing to look into specific information in connection with the accusations, its foreign ministry said, adding that Canada has not shared anything so far.
A blanket suspension of new visas by India for a Western country is unheard of and marks the lowest point of India-Canada relations.
The announcement yesterday came hours after Canada's high commission in India said it would temporarily "adjust" staff presence in the country after some diplomats received threats on social media platforms.
The mission did not specify the nature of the threats, and India has said it would provide "all security and all support" to foreign diplomats.
Indian foreign ministry spokesperson Arindam Bagchi said India suspended issuing new visas to Canadian citizens due to "security threats" to its staff in its consulates in Canada.
India did not give details of the nature of these security threats, and Canada's public safety minister Dominic LeBlanc said in response that Canada was a safe country.
"Accordingly our high commission and consulates are temporarily unable to process visa applications," he told reporters at a weekly briefing yesterday, adding that the security situation would be reviewed regularly.
Canada is the fourth largest source of foreign tourists with 350,000 visitors in 2019, a number which fell following the Covid-19 pandemic, according to Indian government data.
The unprecedented tensions flared up on Monday after Mr Trudeau said Ottawa was investigating "credible allegations" about the potential involvement of Indian government agents in the June murder of Hardeep Singh Nijjar in British Columbia.
India Prime Minister Narendra Modi's government denied any links to the alleged murder.
Canadian officials have so far declined to say why they believe India could be linked to Mr Nijjar's murder.
The two countries, whose relations have been fraying in recent years over the issue of Sikh separatists, have since announced tit-for-tat expulsions of senior diplomats and issued tit-for-tat travel advisories.

Mr Bagchi said India was "willing to look at any specific information, we have conveyed this to the Canadian side, made it clear to them ... but so far, we have not received any such specific information".
Canada has discussed the issue with key allies such as the Five Eyes intelligence sharing alliance, which includes the United States, Britain, Australia and New Zealand, with Washington, London and Canberra expressing concern.
Asked if any of these countries, with whom India also enjoys close ties, had raised the issue with New Delhi, Mr Bagchi said: "We have been discussing with them, we have conveyed our position how we see these developments."
Mr Bagchi also said Canada should be worried about damage to its reputation and not India, when asked about the risk posed by the row to New Delhi's global standing.
"If there is any country that needs to look at it, it is Canada, its growing reputation as a safe haven for terrorists, extremists and for organised crime," he said, adding that India had in vain sought action against more than 20 individuals.
India has not provided any details of acts of terrorism carried out by Sikh separatists against its interests in Canada.