LONDON: Russia's invasion of Ukraine is a catastrophe for Europe, British Prime Minister Boris Johnson said on Thursday, calling for an urgent meeting of NATO leaders and setting out plans to make a public address and speak to G7 leaders.

"This is a catastrophe for our continent," he said on Twitter. "I will make an address to the nation this morning on the Russian invasion of Ukraine."

Bloodshed and tears as eastern Ukraine faces Russian attack

"I will also speak to fellow G7 leaders and I am calling for an urgent meeting of all NATO leaders as soon as possible."