NATO assures Ukraine open-ended military support against Russia

NATO on Sunday pledged open-ended military support for Ukraine, as Finland hailed its "historic" bid to join the alliance and with Western claims that Russia had suffered heavy losses in its push east.

The promise came after Finland jettisoned decades of military non-alignment for a bulwark against Russia, redrawing the balance of power in Europe and angering the Kremlin.

On the ground in Ukraine, Russia announced air strikes in the east, as well as in Lviv, near the Polish border in the west which has largely been spared the destruction of elsewhere.

At a meeting of alliance foreign ministers in Berlin, Germany's Annalena Baerbock said it would provide military assistance "for as long as Ukraine needs this support for the self-defence of its country".

"Ukraine can win this war. Ukrainians are bravely defending their homeland," NATO chief Jens Stoltenberg added.

Finland's move to join NATO is expected to be followed by neighbouring Sweden as soon as Monday, despite concerns from member state Turkey which has accused both countries of harbouring Kurdish extremists. 

Stoltenberg said the alliance would look to provide both with interim security guarantees while the applications are processed, including possibly by increasing troops in the region.

The Kremlin insists the Nordic nations have nothing to fear, in apparent retaliation, has pulled the plug on electricity supplies to Finland, with which it shares a 1,300-kilometre border.