NATO's chief said on Friday the Western military alliance would not set up a no-fly zone over Ukraine nor send its troops there, but promised other help to Kyiv and urged President Vladimir Putin to end immediately Russia's invasion.
"This is President Putin's war, one he has chosen, planned and is waging against a peaceful country. We call on President Putin to stop this war immediately, withdraw all his forces without conditions and engage in genuine diplomacy now," NATO Secretary General Jens Stoltenberg told a news conference.
After a meeting of NATO foreign ministers, Stoltenberg also said: "Allies agree we should not have NATO planes operating in Ukrainian air space or NATO troops on Ukraine's territory."
He said Russia's was in Ukraine was "horrific".
"At the same time, we have a responsibility as NATO allies to prevent this war from escalating beyond Ukraine because that would be even more dangerous, more devastating and would cause even more human suffering."
Ukrainian Foreign Minister Dmytro Kuleba addressed the alliance via videolink from Kyiv.
He tweeted afterwards: "My message: act now before it's too late. Don't let (Russian President Vladimir) Putin turn Ukraine into Syria. We are ready to fight. We will continue fighting. But we need partners to help us with concrete, resolute and swift actions, now."
NATO members have rushed thousands of troops to eastern Europe to bolster the alliance's flank closest to Russia and are sending weapons to help Ukraine defend itself.
Kyiv has said that if NATO is not willing to shut Ukrainian airspace then the allies should supply warplanes and air defence systems to help stop Russian air attacks.
European nations have so far said they will not deliver planes and most arms deliveries have focused on light weapons, and anti-tank and shoulder-fired anti-aircraft missiles.
