AIRCRAFT flying to or from UK airports are being ordered to avoid Ukraine airspace after the crisis intensified on Thursday.

During a televised address, Vladimir Putin announced action on Ukraine saying the move was a response to threats from Ukraine.

Transport Secretary Grant Shapps said he made the decision “following the horrific events overnight” as Russia launched a major military assault.

The Cabinet minister tweeted: “I’ve instructed @UK_CAA (the Civil Aviation Authority) to ensure airlines avoid Ukraine airspace to keep passengers and crew safe.

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“We continue to stand with the people of Ukraine and work with our international partners to respond to this act of aggression.”

Wizz Air has also cancelled its flights from the Ukrainian cities of Kyiv and Lviv to Luton on Thursday, February 24 as the crisis worsens.

On Tuesday, Foreign Secretary Liz Truss urged British nationals in Ukraine to “leave now via commercial routes while they are still available”.

Putin has accused the US and its allies of ignoring Russia’s demand to prevent Ukraine from joining Nato and offering Moscow security guarantees.

He said the Russian military operation aims to ensure a “demilitarisation” of Ukraine, adding that all Ukrainian servicemen who lay down arms will be able to safely leave the zone of combat.

Prime Minister Boris Johnson said Russian President Vladimir Putin has “chosen a path of bloodshed and destruction” with his attack on Ukraine and that the UK and its allies would respond “decisively”.

A Downing Street spokesperson said the Prime Minister will chair a Cobra committee meeting at 7.30am to discuss the response to the “horrific attacks”.