The Wyre and Preston North MP said he did not “want to see British people killed any more than I want to see Ukrainians” dying after Cabinet colleague Liz Truss said she would “absolutely” support British nationals who chose to go to help fight against the Russian invasion.
Ukrainian President Volodymyr Zelensky has announced the formation of a new “international legion” to help defend his country and appealed to foreign volunteers to come forward, promising them arms to fight against the Russian troops.
Asked on the BBC’s Sunday Morning programme if she would support UK citizens who chose to answer the call, Foreign Secretary Ms Truss said: “That is something people can make their own decisions about.
“Absolutely, if people want to support that struggle I would support them in doing that.”
But Mr Wallace, who served in the Scots Guards, said there were “better ways” for Britons to help.
Mr Wallace told Sky News Ms Truss was right that it was a “just cause”, but added: “If you’re keen to help and you’re a United Kingdom citizen, come and join our armed forces.
“Look, there are people who will go… I think what I would say is unless you are properly trained, unless you are a, you know, experienced member of an armed forces, I think there are better ways for you to contribute to the security of Ukraine.”
He said this could be through donating money through the Ukrainian embassy to be spent on weaponry and aid, or to volunteer with organisations helping refugees.
Mr Zelensky’s call for an international legion carried echoes of the International Brigades that fought against the fascists – backed by Nazi Germany – in the Spanish Civil War in the 1930s.
Ukrainian foreign minister Dmytro Kuleba appeared to encourage the comparison, saying that just as Hitler had finally been defeated, “we will defeat Putin, too”.
“Foreigners willing to defend Ukraine and world order as part of the International Legion of Territorial Defence of Ukraine, I invite you to contact foreign diplomatic missions of Ukraine in your respective countries,” he tweeted.
“Together we defeated Hitler, and we will defeat Putin, too.”
Mr Wallace was asked on LBC whether, with his military experience, he would head to Ukraine if he was not a Government minister.
He said although he would “always fight for my country”, he joked that he would “probably be reduced by now to be in charge of, at my age, the Home Guard or something”.
But he said the situation in Ukraine was “very dangerous” and citizens should find other ways to support the country.
Armed forces minister James Heappey was asked on Good Morning Britain whether he would echo Ms Truss’s words, and said: “I probably wouldn’t. And I think that the travel advice is that UK nationals should not travel to Ukraine.
“But if people are filled with a desire to stand up for freedom, like generations of young people before them, they would be very, very welcome at their nearest Army, Navy, Air Force recruiting office,” he said.
“I just think people have to have their eyes wide open to what war is and it is not somewhere that you just jump on a plane, grab a rifle and get going.
“The people that you see doing that in Kyiv are doing it because they are facing an existential threat, out of absolute desperation.”
There have been questions about the legality of Britons going abroad to fight in previous foreign conflicts.
In 2014, the Crown Prosecution Service warned that UK nationals who went to fight in the Syrian civil war could be committing an offence, even if they joined the rebels fighting to overthrow President Bashar Assad.