British forces could give support and training to Ukrainians in their battle against Vladimir Putin’s “invasion”, James Heappey suggested.
But personnel would have to be kept away from the frontline, to prevent sparking a conflict between Russia and NATO.
He also warned the UK’s armed forces were running “incredibly hot” and that the UK had to be better prepared for a potential war, amid growing threats around the world.
One way of achieving this could be through a large “strategic reserve” force of thousands of veterans, who could be called up at a time of national crisis, he said in an interview with Sky News.
Asked about the possibility of western troops on the ground in Ukraine, he stated: “I think you’ve got to be careful about how you do it. I think definitely nowhere near a combat zone. I think you’ve got to be very, very careful not to make it into a Russo-NATO war.
“But I do think it is worth exploring what in the sort of deeper – in the depth of Ukraine – the donor community could do.”
On British troops on a training mission inside Ukraine, he added: “I think it is worth considering.”
The ex-minister, who stepped down from his role last month, warned that if personnel were pushed “too hard” many could leave.
He told Sky News: “The reality is is that we are running them incredibly hot.”
He also predicted “we are going to be running our forces as busy as they are for a very long time to come and if we are going to do that, bearing in mind that they have an absolute right to leave when we push them too hard and lots of them are, we need a bigger force in order to be able to meet the ambition”.
Heappey has urged Rishi Sunak to increase defence spending now to 2.5 per cent of GDP.
Another former defence minister said any deployment of UK troops to Ukraine would have to be done as part of a wider coalition.
“If we were to send any troops ourselves, I think it would need to be done as part of a coalition,” Tobias Ellwood stated, adding, “The call by Ukraine right now is actually not for personnel, it is desperately for equipment.”
Earlier this week President Zelensky warned Ukraine would “will lose the war” if the United States Congress did not approve billions in military aid being held up by Republican politicians.
