Europe is witnessing “destruction not seen since the Second World War”, Nato chief Jens Stoltenberg has warned.
In a speech in his native Norway, Mr Stoltenberg insisted the alliance has a “moral responsibility” to support Ukraine as the conflict rages on.
“They are an independent country, with over 40 million people, who are unjustifiably subject to a brutal war of aggression.
“We are seeing acts of war, attacks on civilians and destruction not seen since World War II,” Mr Stoltenberg said.
Despite threats made against the alliance by the Russian president, Mr Stoltenberg said Nato’s purpose “is not to provoke a war” but to “prevent” one.
With Russia continuing its brutal invasion of Ukraine, Mr Stoltenberg said Nato’s place is now more “important than ever”, in what he called a “more dangerous world”.
He added: “It is more important now than ever, in a more dangerous world with war in Europe.
“Where Russia has invaded Ukraine, President Putin has attacked an entire innocent country and people, with military force, to achieve his political goals.”
His speech comes as the US senate approved Nato membership for Finland and Sweden.
In order to join the alliance, all Nato-member states must vote to approve new members.
US President Joe Biden said: “This historic vote sends an important signal of the sustained, bipartisan US commitment to Nato, and to ensuring our Alliance is prepared to meet the challenges of today and tomorrow.”