The UK and the US have expressed concerns over the departure of 41 Canadian diplomats from India, with Britain saying it disagrees with Indian government decisions which it believes is behind their exit amid an ongoing standoff between India and Canada over the killing of a Sikh separatist.

While a statement from the UK's Foreign, Commonwealth and Development Office (FCDO) on Friday said the move impacted the effective functioning of the Vienna Convention on Diplomatic Relations, the US State Department stressed that resolving differences requires diplomats on the ground.

The separate statements came after Canada said it had withdrawn 41 diplomats following an alleged Indian threat to unilaterally revoke their status amid strained bilateral relations over Prime Minister Justin Trudeau’s claims of Indian agents being involved in the June murder of Hardeep Singh Nijjar, a Canadian Sikh.

In New Delhi, the Ministry of External Affairs (MEA) has strongly rejected the allegation and also refuted any violation of the Vienna Convention in relation to the Canadian diplomats' exit.

"We reject any attempt to portray the implementation of parity as a violation of international norms," the MEA statement said.

In London, the FCDO statement pointed out that "resolving differences requires communication and diplomats in respective capitals." "We do not agree with the decisions taken by the Indian government that have resulted in a number of Canadian diplomats departing India,” it said.

“We expect all states to uphold their obligations under the 1961 Vienna Convention on Diplomatic Relations. The unilateral removal of the privileges and immunities that provide for the safety and security of diplomats is not consistent with the principles or the effective functioning of the Vienna Convention. We continue to encourage India to engage with Canada on its independent investigation into the death of Hardeep Singh Nijjar,” it said.

The UK’s statement followed the US government also backing Canada over the standoff.

US State Department Spokesperson Matthew Miller said: “We are concerned by the departure of Canadian diplomats from India, in response to the Indian government’s demand of Canada to significantly reduce its diplomatic presence in India. Resolving differences requires diplomats on the ground.

“We have urged the Indian government not to insist upon a reduction in Canada’s diplomatic presence and to cooperate in the ongoing Canadian investigation.” The MEA on Friday rejected all attempts to portray the implementation of diplomatic parity as a violation of international norms.

''The state of our bilateral relations, the much higher number of Canadian diplomats in India, and their continued interference in our internal affairs warrant a parity in mutual diplomatic presence in New Delhi and Ottawa,'' the MEA said.

The row was triggered following Trudeau’s statement in the Canadian Parliament last month that its security forces were "actively pursuing credible allegations" linking Indian government agents to the murder of Khalistan Tiger Force leader and wanted terrorist in India Hardeep Singh Nijjar, an allegation strongly rejected by the MEA as “absurd and motivated”.

On Friday, Trudeau told reporters in a televised press conference that the Indian government is making it “unbelievably difficult” for life as usual to continue for millions of people in India and in Canada. Earlier, the Canadian authorities also warned of a slowdown in visa processing times due to the reduction of employees at its diplomatic mission in India.

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