Outgoing European Council president Donald Tusk has urged Remain campaigners not to "give up" in their fight to stop Brexit.
Mr Tusk said Brexit will lead to the UK becoming “an outsider" and suggested it could lead to “the real end of the British Empire”.
He made the comments in a speech at the opening of the College of Europe as his second term as president draws to close.
“The UK election takes place in one month. Can things still be turned around?" he said.
“Hannah Arendt taught that things become irreversible only when people start to think so.
“So the only words that come to my mind today are simply: Don’t give up.
“In this match, we had added time, we are already in extra time, perhaps it will even go to penalties?”.
David Davies said foreign leaders should "stay out" of the Brexit debate
The Brussels chief, who is stepping down after five years in the job, said he “wouldn’t have dared” to share his opinion few months ago for fear he could have lost his job “for being too frank”.
He added that he envied former Commons Speaker John Bercow because, since leaving the role, “he can finally, honestly say what he thinks about Brexit”.
Liberal Democrat shadow foreign secretary Chuka Umunna said the remarks show “light at the end of the tunnel” for Remain supporters.
However, Conservative election candidate and former Brexit Secretary David Davis criticised Mr Tusk for commenting on the debate.
He tweeted: “Donald Tusk is unwise to ignore the convention of staying out of internal politics of member states.
“Foreign leaders should stay out of our democratic decisions, whether they are Obama, Trump or Tusk.”
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