British veterans and troops must not travel to Ukraine as they could risk dragging the UK into the conflict, a Tory minister has said.
Armed Forces Minister James Heappey blasted serving soldiers who have gone AWOL to join the fighting and said it is "illegal" and "100% not the correct thing to do".
Three or four members of the British forces have gone out to fight in Ukraine, he confirmed, and warned Vladimir Putin could claim the UK was being "belligerent".
Mr Heappey, a former Army major, also explicitly warned veterans not to travel out to fight the Russians, saying: "No good comes from British service people or veterans going to Ukraine to be a part of this."
His comments come amid mounting criticism of Foreign Secretary Liz Truss, who initially said she would "absolutely" support British volunteers going out to join the conflict.
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Ms Truss rowed back on her comments on Wednesday, saying she was "expressing support for the Ukrainian cause".
Her Tory colleague Mr Heappey said those involved will be "in an awful lot of trouble".
"It is illegal for British service personnel to first of all go absent without leave in the first place," he told Sky News.
"To go absent without leave in order to fight in a foreign war is simply unacceptable, and frankly risks the United Kingdom being wrongly claimed by Russia to be a belligerent in this.
"Service people who might think they are doing the right thing should reflect it is 100% not the correct thing to be doing."
He said only a "very small number of soldiers" had gone AWOL - but he issued a warning to veterans also thinking of joining the fight.
Mr Heappey said: "I would say to the wider veterans community I know ... that there's a thing deep inside you as a soldier that makes you see TV images and makes you want to go and fight for what's right, but no good comes from British service people or veterans going to Ukraine to be a part of this."
Mr Heappey added: “This is not the time for people to be going there and, more importantly, as Ukrainians have made clear, once you’ve crossed the border with the expectation to fight, you’re in it for good.
“So people who think they can go there for a couple of weeks, take some selfies, get some Instagram shots and then come home, that is not the way that the Ukrainians are viewing the people that go to fight for them. British people should not be doing it.”
The top Tory also accused Russia of committing a war crime by striking a maternity hospital in Mariupol.
He told BBC Breakfast: "Was it an indiscriminate use of artillery or missiles into a built-up area, or was a hospital explicitly targeted?
"Both are equally despicable, both, as the Ukrainians have pointed out, would amount to a war crime."
An Army spokesperson told Sky News: "We are aware of a small number of individual soldiers who have disobeyed orders and gone absent without leave, and may have travelled to Ukraine in a personal capacity.
"We are actively and strongly encouraging them to return to the UK."
All serving personnel are banned from travelling to Ukraine, whether on leave or not - and will face disciplinary consequences if they flout the order, the spokesperson said.
