Updating its travel advisory amid escalating tension, Canada has reportedly asked its citizens to "exercise caution" while travelling to India.

A special mention has reportedly been made about Jammu & Kashmir. The advisory reads, "The security situation in the Union Territory of Jammu and Kashmir is tense. There are high risks of violent protests, civil unrest and acts of terrorism and militancy."

Trudeau reacts again

Canadian PM Justin Trudeau said on Tuesday that Ottawa decided to speak now because "we wanted to make sure that we had a solid grounding in understanding what was going on ... we wanted to make sure we were taking the time to talk with our allies."

He told reporters that the case had far-reaching consequences in international law.

"The government of India needs to take this matter with the utmost seriousness. We are doing that; we are not looking to provoke or escalate," he said.

The affair has derailed protracted talks on a potential bilateral trade deal.

A source familiar with the situation said Canada's decisions on Sept. 1 to pause the talks and on Sept. 15 to postpone a major trade mission set for next month, had been directly linked to concerns over the murder.

The source spoke on the grounds they not be identified, since they were not authorised to speak to reporters.

Canadian officials have so far declined to say why they believe India could be linked to Nijjar's murder.