The European Union (EU) has said it will buy and deliver weapons to Ukraine.

"For the first time ever, the European Union will finance the purchase and delivery of weapons and other equipment to a country that is under attack," European Commission President Ursula von der Leyen said on Sunday. "This is a watershed moment."

Josep Borrell, the European Union's high representative for foreign affairs and security policy, said the foreign ministers of EU member states have agreed to provide Ukraine with lethal weapons worth 450 million euros, plus 50 million euros for non-lethal supplies, fuel and protective equipment.

"This is the first time in history that we will be doing that and everybody agreed to at least not obstruct this decision," Borrell said.

Apart from military aid to Ukraine, the EU on Sunday announced other steps including closing EU airspace to Russia, a media ban on Russia Today and Sputnik, as well as strengthening sanctions against Russia and Belarus, which the EU said is "the other aggressor" in the crisis in Ukraine.

In a statement, Von der Leyen said that the EU will also ban the transactions of Russia's central bank and freeze all its assets, and target the assets of Russian oligarchs.