NATO on Friday rejected Ukrainian calls to help it protect its skies from Russian missiles and warplanes, wary of being dragged into Moscow's war on its neighbour, but Europe promised more sanctions to punish Russian President Vladimir Putin.

Ukrainian President Volodymyr Zelenskiy strongly criticised the decision, saying the alliance had given Russia the green light to continue its bombing campaign.

He had earlier appealed to NATO to set up a no-fly zone over Ukraine, which Russia invaded by land, sea and air on Feb. 24.

"We are not part of this conflict," NATO Secretary General Jens Stoltenberg said in denying Ukraine's request.

"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," he said following a NATO meeting in Brussels.

Ukraine, a former Soviet republic, wants to join the European Union and NATO, moves which Moscow says threaten its security and influence. Russia has shelled residential areas and civilian infrastructure, as well as capturing two nuclear sites.

"Today there was a NATO summit, a weak summit, a confused summit, a summit where it was clear that not everyone considers the battle for Europe's freedom to be the number one goal," Zelenskiy said a televised address late on Friday.

"Today, the leadership of the alliance gave the green light for further bombing of Ukrainian cities and villages, having refused to set up a no-fly zone."

While the West condemned Putin, members of the 30-strong NATO are bound to defend each other in case of attack and wary of sinking into a war with nuclear-armed Russia. The EU threatened more sanctions but it was not clear what it could do.

U.S. Secretary of State Antony Blinken said the alliance would defend "every inch" of NATO territory and that Moscow should not doubt Washington's resolve.

"Ours is a defensive alliance. We seek no conflict. But if conflict comes to us, we are ready," he said.

"We'll continue to raise the cost for President Putin. Unless the Kremlin changes course, it will continue down the road of increasing isolation and economic pain."

But the alliance - in which the United States, Britain and France are also nuclear powers - dashed Ukraine's hopes of immediate help Kyiv says could turn the tables in the war.

"We should not have NATO planes operating over Ukrainian airspace or NATO troops operating in Ukrainian territory," Stoltenberg said.


Support for Ukraine so far has come in the form of the heaviest international economic sanctions against Russia to date, as well as arms supplies from NATO states.

On Friday, the West promised Ukraine more humanitarian aid, essential supplies and military support short of going to war.

In a day of intense diplomacy - if no obvious immediate results - the G7 countries said they would hold accountable those responsible for war crimes and refuse to recognise any Russian territorial gains.

EU countries said more punishment was coming, after the bloc already cut several Russian lenders from the SWIFT banking system, curbed trade with Moscow and targeted some of the wealth held by Russian oligarchs in the West.

The EU was looking at curbing Russia's access to the International Monetary Fund, officials said.

"It's Putin's war, and only Putin can end it," the top EU diplomat, Josep Borrell, said. "If someone expects that sanctions can stop the war tomorrow, they don't know what they're talking about."

Ukraine called on the West to freeze out all Russian banks. But it was not clear when and what more sanctions the EU could agree, given its reliance on Russian energy supplies, which think tank Eurointelligence said amount to $700 million daily.

Stoltenberg said the worst was yet to come as Russia was rolling out more heavy arms.

"The days to come are likely to be worse, with more deaths, more suffering and more destruction," he said.