The UK must be braced for repercussions, including cyber attacks, after standing up to Russia, the Prime Minister has warned.

Boris Johnson told MPs Britain is offering “unwavering support” to Ukraine, telling the Commons “slava Ukraini”, which translates as “glory to Ukraine”.

But he warned on Thursday that the West will face consequences for standing with the country.

He said: “Last Saturday, I warned that this invasion would have global economic consequences and this morning the oil price has risen strongly.

“The Government will do everything possible to safeguard our own people from the repercussions for the cost of living.

“And, of course, we stand ready to protect our country from any threats including in cyberspace.”

Foreign Secretary Liz Truss earlier said Russia had launched cyber attacks on Ukraine.

Home Secretary Priti Patel said British officials were on alert for such attacks, plus disinformation campaigns.

She tweeted: “Russia’s unjustified and unjustifiable attack on a democratic sovereign nation makes this a dark day in Europe. The people of Ukraine have our unwavering support.

“As we monitor developments, we will be especially mindful of the potential for cyberattacks and disinformation emanating from Russia.

“Be in no doubt there is work ongoing across government 24/7 to maximise our resilience to any such attacks, which would be met with a suitably robust response.”

Labour leader Sir Keir Starmer also said there would be difficulties at home, but he added: “The British public have always been willing to make sacrifices to defend democracy on our continent and we will again.

“We will face economic pain as we free Europe from dependence on Russian gas and clean our institutions from money stolen from the Russian people.”

He added: “The consequences of Putin’s actions will be felt throughout the world for years – and I fear decades – to come.”