Expanding NATO squares up to Russia threat

The United States vowed to shore up Europe's defences in the wake of Russia's invasion of Ukraine, as NATO declared Moscow the West's greatest threat.

Meeting in Madrid, alliance leaders said Russia "is the most significant and direct threat to allies' security and to peace and stability in the Euro-Atlantic area".

This came as NATO welcomed Sweden and Finland as invitees to join the alliance and US President Joe Biden announced new deployments of US troops, ships and planes.

Biden boasted the US announcement was exactly what President Vladimir Putin "didn't want" and Moscow, facing fierce resistance from Ukrainian forces equipped with Western arms, reacted with predictable fury.

"Ukraine can count on us for as long as it takes," NATO chief Jens Stoltenberg said, announcing a new NATO strategic overview that focuses on the Moscow threat.

"We cannot discount the possibility of an attack against allies' sovereignty and territorial integrity," the document, updated for the first time since 2010, said.

In a summit statement, they said: "Russia's appalling cruelty has caused immense human suffering and massive displacements, disproportionately affecting women and children."

Zelensky had earlier addressed the NATO chiefs by videoconference, calling for stricter economic sanctions.