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The UK's defence secretary has spoken out against calls for Britons to join fighting in the Ukraine, after Foreign Secretary Liz Truss offered her open support to British citizens who wanted to join the conflict.
Ben Wallace said the “very dangerous” situation could lead to them being killed.
His comments came after Ms Truss said she would “absolutely” support citizens who chose to go and fight.
On Sunday, Ukrainian President Volodymyr Zelenskyy 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 Russian troops.
“This is the beginning of a war against Europe, against European structures, against democracy, against basic human rights, against a global order of law, rules and peaceful coexistence,” a statement on the president's website said.
“Anyone who wants to join the defence of Ukraine, Europe and the world can come and fight side by side with the Ukrainians against the Russian war criminals.”
Ukrainian Foreign Minister Dmytro Kuleba also urged the international community to join the country's forces.
“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.”
Following his call to arms, Ms Truss said she would support UK citizens who wanted to help.
“The people of Ukraine are fighting for freedom and democracy, not just for Ukraine but for the whole of Europe," she told the BBC.
“If people want to support that struggle I would support them in doing that.”
However, on Monday Mr Wallace, who once served in the armed forces, openly hit out at her comments and said he did not “want to see British people killed any more than I want to see Ukrainians” dying and said there were "better ways" to support Ukraine.
“If you’re keen to help and you’re a United Kingdom citizen, come and join our armed forces," he told Sky News.
“Look, there are people who will go… I think what I would say is unless you are properly trained, unless you are an 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.
His comments were echoed by Armed Forces Minister James Heappey who said he "probably wouldn't" support Ms Truss's remarks.
“I think that the travel advice is that UK nationals should not travel to Ukraine," he said.
“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.
“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 Kiev 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, prosecutors gave a warning that UK citizens 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 Al Assad.
On Monday, Latvia’s parliament voted unanimously to amend its national security law to allow its citizens to voluntarily travel to Ukraine to fight.
“Our citizens, who want to support Ukraine and voluntarily go there to serve, to defend Ukraine’s independence and our common security, must have the possibility to do so,” Juris Rancans, chairman of the parliamentary committee responsible for the law, said.