Boris Johnson is preparing to send a “clear message” to Russia by increasing the number of troops the UK deployed across Europe.
The prime minister said the armed forces deployment planned by Britain will “support our NATO allies on land, at sea and in the air”.
Johnson, who said the UK would “not tolerate” Russia’s “destabilising activity”, admitted an incursion from Moscow into Ukraine would be a “tragedy”.
Meanwhile, the government confirmed the UK may send defensive weapons to Estonia as well as fast jets, warships and military specialists to protect NATO allies.
Downing Street said the potential deployment would “reinforce Nato’s defences and underpin the UK’s support for Nordic and Baltic partners”.
Johnson is set to talk to Russia’s president, Vladimir Putin, early this week, as well as to NATO members in a separate trip.
And, while ministers will discuss their military options on Monday, Johnson has already asked foreign secretary Liz Truss and defence secretary Ben Wallance to go to Russia and also speak to their counterparts soon, in order to encourage de-escalation.
Currently, Britain has over 100 troops giving training in Ukraine and 900 military personnel in Estonia, as well as around 150 army people in Poland.
“This package would send a clear message to the Kremlin – we will not tolerate their destabilising activity, and we will always stand with our Nato allies in the face of Russian hostility,” Johnson said.
He added: “If President Putin chooses a path of bloodshed and destruction, it will be a tragedy for Europe. Ukraine must be free to choose its own future.
“I have ordered our Armed Forces to prepare to deploy across Europe next week, ensuring we are able to support our Nato allies on land, at sea and in the air.”
Foreign secretary Liz Truss has previously warned Russia of “severe sanctions” if they invade Ukraine.
“They would target individuals, they would target financial institutions and they would be co-ordinated with all of our allies across Europe, the United States and others,” she said.
This week, Truss told BBC Radio 4 that the government had “ruled nothing out” when it comes to personal sanctions against Putin.
And she told Sky News: “We are already supplying support to Ukraine. We’re supplying defensive weapons. We’re providing economic support.
“We are urging Russia to desist from an incursion and we’re making it very clear that if they were to do that there would be severe economic cost to Russia – severe sanctions.”
Meanwhile, Labour accused Johnson of “playing catch-up with other world leaders” on deterring Russian aggression against Ukraine.
The government is “paralysed by a mess of its own making” domestically as a result of the ongoing Partygate scandal engulfing Downing Street, shadow defence secretary John Healey said.
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