Ottawa is advising Canadians against traveling to Ukraine due to Russian threats and the risk of war.
The federal government is also urging Canadians currently in that country to leave.
The warning comes amid growing tensions between Russia and the West over the deployment of 100,000 Russian troops to the Ukrainian border.
Talks between the United States, NATO and other Canadian allies and Russia have so far proved fruitless, raising fears of another war in Europe.
Canada had advised against non-essential travel to Ukraine and recalled some diplomatic staff and their families in recent weeks.
But the intensified warning suggests growing concerns that a conflict is about to break out, even as negotiations continue.
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