Commission President Ursula von der Leyen said the bloc would, for the first time in its history, "finance the purchase and delivery of weapons and other equipment to a country that is under attack".
She also said that three new tranches of sanctions would be introduced. They are:
Banning all Russian aircraft from its airspace
"We are shutting down the EU airspace for Russians," von der Leyen said.
"We're proposing a prohibition on all Russian-owned, Russian-registered, and Russian-controlled aircraft.
"These aircraft will no more be able to land in, take off, or overfly the territory of the European Union."
She said the move would also cover the private jets of Russian oligarchs.
Banning what von der Leyen called the "Kremlin's media machine"
"The state-owned Russia Today and Sputnik, as well as their subsidiaries, will no longer be able to spread their lies to justify Putin's war," she said.
"We are developing tools to ban that toxic and harmful disinformation in Europe".
Widening its existing sanctions to target Belarus
"Lukashenko's regime is complicit in the vicious attack against Ukraine," she said.
She said the sanctions would target Belarus's "most important sectors" and export products.
The European Union has announced that it intends to begin shipping arms to Ukraine, the first time in its history it has taken such a step.
Speaking at a press conference this afternoon, European Commission President Ursula von der Leyen said the move marked a "watershed moment".
She also announced a raft of new sanctions targeting Russia and Belarus, and a ban on Russia using European airspace.
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