The United States on Friday expressed concern over the departure of Canadian diplomats from India and said that it expects New Delhi to uphold its obligations under the 1961 Vienna Convention on Diplomatic Relations.

Canada has withdrawn 41 diplomats from India after it threatened to strip them of their diplomatic immunity by Friday, Foreign Affairs Minister Melanie Joly has said, amid a diplomatic row over the killing of a Sikh separatist.

“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,” State Department Spokesperson Matthew Miller said.

"Resolving differences requires diplomats on the ground," Miller added.

“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 State Department official said.

“We expect India to uphold its obligations under the 1961 Vienna Convention on Diplomatic Relations, including with respect to privileges and immunities enjoyed by accredited members of Canada’s diplomatic mission,” Miller said.

In New Delhi, the Ministry of External Affairs on Friday rejected Canada's attempt to "portray" the withdrawal of 41 Canadian diplomats from the country as a violation of international norms.

India asserted that ensuring two-way diplomatic parity is fully consistent with the provisions of the Vienna Convention on diplomatic relations.

Hours after New Delhi rejected Ottawa's attempt to portray the implementation of parity as a violation of international norms, Canada's Prime Minister Justin Trudeau said on Friday that India's decision to revoke the diplomatic immunity of 41 Canadian diplomats is a violation of the Vienna Convention and it should worry all countries.

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