An aircraft carrier which carries Norfolk stealth fighters is on stand-by to sail within hours if tensions escalate further over Ukraine.

Foreign secretary and South West Norfolk MP Liz Truss is preparing to fly to Moscow to meet her Russian counterpart in a bid to defuse the stand-off.

Boris Johnson has warned Russian president Vladimir Putin that invading Ukraine would backfire and only serve to strengthen Nato.

Mr Johnson, writing in the Times, said the UK "will not flinch now" and that Britain will remain "unconditional and immovable" in supporting the Nato defence alliance.

"If he launches another invasion, he will force the West to bring about much of what he seeks to prevent. In fact this is already happening.

"Because of his build-up, America, France, Italy and other allies are deploying forces to Nato's south-eastern flank, just as the UK reinforces the northeast."

An estimated 130,000 Russian troops have been massing on Ukraine's border.

While Nato countries have not sent forces to Ukraine, which is not a member, they have pledged to support neighbouring nations including Poland, where a further 350 British troops are set to join 100 already there.

Around 3,000 American personnel are also being deployed to eastern Europe.

The 65,000-tonne Prince of Wales was appointed the command ship of Nato's Maritime High Readiness Force in January. The ship is currently moored at its home port of Portsmouth.

Mr Johnson announced earlier this week that the carrier, which carries F-35 Lightning jets from RAF Marham, was on alert to be deployed in response to the ongoing crisis in eastern Europe as part of a wider UK military contribution to support Ukraine.

"It is on standby to move within hours should tensions rise further," he said in a statement issued by Downing Street.

The UK has taken over from France to run the Nato task force which is formed to deal with major global incidents.

Ms Truss has scheduled a trip to Russian capital to meet with her counterpart, Sergei Lavrov.

She missed a trip to Ukraine with the prime minister last week after testing positive for Covid-19.

European leaders are also due to travel to both Moscow and Kyiv in a bid to calm tensions on the Ukrainian border.