The US encouraged its nationals in Russia to “consider” leaving immediately on Sunday, as commercial airlines canceled flights and countries shut their airspace in a move to punish Moscow for invading Ukraine.

In a statement, the US embassy in Moscow claimed, “an increasing number of airlines are canceling flights into and out of Russia, and other nations have blocked their airspace to Russian aircraft.”

“Consider leaving Russia immediately via commercial possibilities still accessible,” it advised its people.

The US embassy, on the other hand, stated that it will not be revising its travel warning for Russia.

As tensions over Ukraine increased, it issued a Level 4 “Do Not Travel” warning against Russia in January.

Outraged by Russian President Vladimir Putin’s murderous assault on Ukraine, the European Union blocked its airspace to Russian planes earlier Sunday.

Many of the EU’s 27 member countries had already announced individual airspace closures to Russian flights, so the move only formalized what was already fully in place.

Canada and the United Kingdom have likewise shut down their airspace.

Russia has also begun blocking its airspace to several European carriers as a form of retaliation.

Meanwhile, Russian airline Aeroflot announced on Sunday that all flights to Europe will be canceled.