Liz Truss has claimed she was "expressing support for the Ukrainian cause" when she said she would "absolutely" support Brit volunteers who chose to fight.
The Foreign Secretary rowed back on the comments she made days after Vladimir Putin's troops invaded Ukraine as she sparked huge backlash.
Speaking at a Washington press conference alongside US Secretary of State Anthony Blinken, Ms Truss said: "I have been very clear that the travel advice from the United Kingdom is not to go to Ukraine.
“There are better ways of helping the efforts in Ukraine, namely donating to the DEC (Disasters Emergency Committee) appeal.
“What I said the other week was expressing support for the Ukrainian cause, they are fighting a just cause and we are doing all we can to support them.”
Want all the latest news and analysis from Ukraine? Sign up to our World News Bulletin here
Hours after she initially made the comments, No10 swiftly distanced themselves from her remarks.
Senior Tory MPs lined up to urge Brits not to go and fight, in a drastic attempt to stop people following Ms Truss's remarks.
In a clear rebuke to the Tory Foreign Secretary, Admiral Sir Tony Radakin urged to support in "whatever way you can" but insisted "it's unlawful as well as unhelpful for UK military and UK population to start going towards Ukraine in that sense".
Defence Secretary Ben Wallace insisted Brits should not to travel to fight as he did not "want to see British people killed any more than I want to see Ukrainians" dying.
Mr Wallace, who served in the Scots Guards, said there are "better ways" for Brits to help Ukrainians.
"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 a, you know, experienced member of an armed forces, I think there are better ways for you to contribute to the security of Ukraine."
Boris Johnson's spokesman said 24 hours after Ms Truss's comments: “We fully recognise the strength of feeling in British people wanting to support Ukrainians."
And pointing to the Foreign Office advice adding: "We firmly advise against travel to Ukraine".
Former Cabinet minister Robert Buckland warned "turning up there with good intentions" and seeking to get involved without any legal authority "could worsen" the situation.
Senior Tory MP and chair of the Commons Defence Committee Tobias Ellwood told the BBC's Politics Live show: "I think she was slightly caught off guard as you saw in the conversation.
"My real concern is that 18 year olds can see this, think they're doing a good thing, think they're well intentioned.
"Please do not go to Ukraine unless you have some form of combat experience."
