A senior NATO official has said Russia's military advance in Ukraine appears to be faltering and he expressed hope that Kyiv can win the war.
Top NATO diplomats are meeting on Sunday in Berlin to discuss providing further support to Ukraine and moves by Finland, Sweden and others to join the western alliance in the face of threats from Russia.
NATO deputy secretary-general Mircea Geoana told reporters: "The brutal invasion (by) Russia is losing momentum.
"We know that with the bravery of the Ukrainian people and army, and with our help, Ukraine can win this war."
Mr Geoana, who was chairing the meeting while NATO's secretary-general Jens Stoltenberg recovers from coronavirus, said Ukraine's supporters are "united, we are strong, will continue to help Ukraine in winning this war".
One key issue being discussed in Berlin is expansion of NATO beyond its current 30 member states.
Watch: How long can war in Ukraine last?
Finland and Sweden have already taken steps towards joining the alliance, while Georgia's bid is again being discussed despite dire warnings from Moscow about the consequences if its neighbour becomes part of NATO.
"Finland and Sweden are already the closest partners of NATO," Mr Geoana said, adding that he expects allies to view their applications positively.
German foreign minister Annalena Baerbock said her country and others made clear during a dinner late on Saturday that they are willing to fast-track the national ratification process for Finland and Sweden.
"If these two countries are deciding to join, they can join very quickly," she said.
Denmark's foreign minister Jeppe Kofod dismissed suggestions that objections from Russian President Vladimir Putin could hinder the alliance from letting in new members.
"Each and every European country has a fundamental right to choose their own security arrangement," he said.
"We see now a world where the enemy of democracy number one is Putin and the thinking that he represents."
He added that NATO will also stand with other countries, such as Georgia, which he said are being "instrumentalised" by Russia.