India and Canada relations at their lowest ever in wake of Sikh leader Hardeep Nijjar's killing

Diplomatic relations between India and Canada have been at their lowest since Prime Minister Justin Trudeau responded to the killing of a Canadian citizen and Sikh separatist leader saying there were "credible allegations" India was involved.

India's government rejected the allegations as absurd and motivated and accused the Canadian government of providing shelter to Khalistan terrorists and extremists that threaten India's sovereignty and territorial integrity.

The allegations that government agents were in some way involved with the hit squad has touched raw nerves.

The accusations lead right up the ladder to India's spy chief, who reports directly to the country's national security advisor Ajit Doval, a close associate and confidant of Prime Minister Narendra Modi.

The Five Eyes, an intelligence-sharing alliance between the US, Britain, Canada, New Zealand and Australia, had provided the information that prompted PM Trudeau to make these allegations. India finds itself in a corner and unable to challenge the alliance.

The allegations caused a diplomatic meltdown last year and relations have not got back on track yet.

We are yet to hear from the government in New Delhi about three Indian nationals being charged in Canada on Friday over Nijjar's death.

Canada expelled the station chief of the Research and Analysis Wing (RAW), India's intelligence agency at India's high commission in Ottawa. India then allegedly threatened to cancel the diplomatic immunity of Canadian officials, resulting in Canada pulling 41 of them out, and suspending issuing visas to Canadian citizens for weeks.

India has exhausted much capital on expulsions of Canadian diplomats. The suspension of visas adversely impacted friends and families of the Indian diaspora in Canada. There was much pressure on Delhi to restrict the spat within the circle of diplomacy rather than involving ordinary people.

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India often accuses Canada of being a safe haven for terrorists and gangsters, and has sought the extradition of several Canadians on terrorist and criminal charges. It claims Canadian authorities have persistently refused to treat these charges seriously.

Speaking to ANI earlier, India's foreign minister Subrahmanyam Jaishankar said: "Canadian politics have given space to Khalistan forces and also allowed them to indulge in activities that adversely impact bilateral relations between India and Canada".

Canada is home to the largest number of Sikhs outside India as they form over 2% of the population, remaining a prominent diaspora and playing a very important role in constituencies in suburban Toronto and Vancouver.

Politicians play diaspora politics without much understanding of its external effects.

Separately, US officials are investigating the potential role of Indian government employees in a foiled assassination plot against another Sikh separatist, Gurpatwant Singh Pannun.

The Indian government set up a high-level inquiry committee last year to look into concerns shared by Washington.

The Khalistan movement is a sensitive subject in India. It took on a militant form in the 1980s and 90s which engulfed the Punjab and parts of north India in a bloody conflict.

In 1984 the Indian Prime Minister Indira Gandhi was assassinated by her Sikh bodyguards as revenge for the violence and desecration of the Golden Temple, the holiest shrine of the Sikhs.

Though the movement finds little resonance in India, its campaign has survived in the West within the large Sikh diaspora.