Canada closes embassy

The Canadian and American embassies in Ukraine are closed to the public today after the U.S. warned of a "potential significant air attack" by Russia in Kyiv.

Ukraine's intelligence agency posted a statement today accusing Russia of spreading fake messages about the threat of an "extremely massive" attack on Ukrainian cities and urging people not to panic.

A message from the U.S. Embassy in Kyiv says it received specific information about a possible attack and out of an abundance of caution, employees are sheltering in place.

Global Affairs Canada's website says in-person services at the Canadian Embassy are temporarily suspended.

Ukraine used U.S.-supplied missiles to strike inside Russia for the first time this week, a move the Kremlin says adds "fuel to the fire" of the war.

U.S. President Joe Biden gave the green light for Kyiv to strike Russian targets and to use antipersonnel landmines, as part of a larger effort to bolster Ukraine's defence before Donald Trump takes over the White House in January.

Trump and his allies have been critical of American funding for Ukraine, stoking fears the president-elect could cut off supplies to the embattled country.

Prime Minister Justin Trudeau told reporters this week that he has long called for allies to give Ukraine permission to strike Russian military targets.

"I have, for months now, talked about how important it is to degrade the capacity of the Russian military to strike into Ukraine with impunity because Ukraine hasn't been able to strike on factories and military production sites in Russia," he said in a press conference in Rio de Janeiro on Tuesday.

Trudeau and Biden discussed Ukraine in a bilateral meeting this week at the G20 leaders' summit.

Trudeau was critical of the G20's final statement, saying it was not strong enough in its support of Ukraine. Russia is a member of the G20 and this year's statement from the leaders did not mention Russia at all.

The BBC reported Wednesday morning that missiles supplied by the U.K. have also been used inside Russia for the first time since the conflict began more than 1,000 days ago.

The Biden administration's move is being seen as an escalation in Moscow.

Asked Tuesday whether a Ukrainian attack with longer-range U.S. missiles could potentially trigger the use of nuclear weapons, Kremlin spokesman Dmitry Peskov answered affirmatively.