France's president mixed up his English when he said in error that UK visitors would need French visas if there was a no-deal Brexit, aides say.
Emmanuel Macron had meant to say that British people would not need visas in such circumstances.
The confusion came as Mr Macron was speaking to the media in English at the end of an EU summit in Brussels.
Instead of "we will not stop visas" he meant to say "we will not start visas", the Elysée Palace explained.
UK citizens currently enjoy visa-free travel in the EU, but that could change with Brexit. The UK is set to leave the 28-nation bloc on 29 March 2019.
The BBC's Gavin Lee raised the visa issue with President Macron at Thursday's news conference, after leaders had failed to achieve a breakthrough on Brexit.
Lost in translation
By Gavin Lee, BBC News, Brussels
The mix-up came after I asked President Macron whether newspaper reports of UK citizens needing visas for work or holidays in the event of a no-deal was true.
The president's response was that "we will not stop visas, it is fake news, as some other leaders would say", and he went on to say "we will definitely deliver visas for people".
His team now say it was a case of a "second language" slip-up, and that President Macron meant to say "we will not start visas for British people".
The press team for the Elysée Palace say the position of the French for their "no-deal" contingency planning is one that would categorically not mean visas for British people, UNLESS the UK suddenly imposed them on French workers and tourists in the UK.
They say they would aim for a deal which allows for a "special status" agreement for workers and tourists for both countries, that avoids the need for any "official visa system".
In the event of a no-deal Brexit, Mr Macron said, measures would be taken to cover flights, ferries and businesses as well.
A draft law has been tabled in the upper house of the French parliament that will let the government set new rules for Britons visiting France after Brexit. The draft suggests they will be treated as "third country" visitors - a similar category to Americans or Chinese. The preamble of the bill raises the possibility that visas may be imposed.
But, in the event of a no-deal Brexit, the bill also gives the government the power to adapt or suspend the need for visas and residence permits for UK citizens.
'Willingness to find solution'
A deal remains elusive mainly because of wrangling over the future Northern Ireland border. Brexit risks reinstating physical controls at the border, which were scrapped under the Northern Ireland peace settlement.
The current Brexit plan is for a transition period of 21 months from the end of March, to smooth the UK's path to a future relationship outside the EU.
UK Prime Minister Theresa May said that transition could be extended "for a few months", if needed. But some Brexit campaigners have reacted angrily to the suggestion.
"I do prefer a deal and I want a deal, but I will never favour a bad deal," Mr Macron said on Thursday.
"In case of no deal our responsibility is to ensure that the life of our people will not be so far impacted."
Mr Macron described the "dynamic" of the Brexit negotiations as "positive because there is a willingness on the British side to find a solution".
He said "now it's for Prime Minister May to propose a solution, but we will not compromise on the key elements of the mandate we gave to [EU negotiator] Michel Barnier".
The French president also denied suggestions that the UK prime minister had been snubbed late on Wednesday, when four EU leaders went out for a drink in the Grand Place in the centre of Brussels.
He told the BBC that Theresa May had left the summit earlier, and said she would certainly be invited in future.
"I am always happy and open to share a drink with the different leaders, so obviously Theresa May will be very much welcome," he said.
Update 19 October 2018: Our story was amended after the Elysée Palace explained that Mr Macron had meant to say "we will not start visas" for British people, but had inadvertently used the verb "stop" instead.