After a meeting that stretched through the afternoon and over dinner, the bloc said Britain could postpone its departure, due on March 29, until May 22 - if the U.K. Parliament approves Prime Minister Theresa May's divorce deal with the bloc next week.
May had wanted to be able to delay Britain's departure until June 30 to tie up legislative loose ends, and tried to reassure the European Union that she could overturn two heavy defeats to clinch a last-gasp parliamentary ratification of her deal next week, so allowing a status-quo transition period to come into effect.
As a result, we will now not leave on time with a deal on 29 March.
"A short extension of Article 50 to the end of June, as I said yesterday, is a matter of personal regret to me".
'You're tired of the infighting, you're tired of the political games and the arcane procedural rows, tired of MPs talking about nothing else but Brexit when you have real concerns about our children's schools, our National Health Service, knife crime.
May told voters tired of a Brexit saga that has dragged on for nearly three years: "You want this stage of the Brexit process to be over and done with".
But he added: "If not, we will have to meet again next week ... we don't rule this out, we also don't welcome it, but I wish that there will be agreement by the British parliament to what Mrs May and I have negotiated last week in Strasbourg".
Earlier, European Council president Donald Tusk said he believed a short delay "would be possible" after he spoke to the Prime Minister by phone. May said it was not in Britain's interests to take part in European elections.
Or do they not want to leave at all, causing potentially irreparable damage to public trust - not just in this generation of politicians, but to our entire democratic process? This position has made it impossible in practice to call a further vote in advance of the European Council.
The vote has left Britain sharply divided
Motion after motion and amendment after amendment have been tabled without Parliament ever deciding what it wants.
The Labour Party said that, by choosing a short delay, May was forcing lawmakers to decide between accepting a deal they have already rejected or leaving without a deal.
The deal has twice been rejected twice by hefty margins in Britain's Parliament, amid opposition from pro-Brexit and pro-EU lawmakers.
If it does not hold the election, leaders said, the very last date Britain must leave would be June 30, before the new European Union parliament convenes.
"There is a case for giving parliament a bit more time to agree [on] a way forward, but the people of this country have been waiting almost three years now".
"With regard to the date of June 30, we have to take into consideration that we have European elections in May".
And that might involve allowing MPs to find a Brexit strategy they agree on, holding a fresh referendum or calling the general election that Labour leader Jeremy Corbyn has been asking for.
I don't believe that is what you want - and it is not what I want. "It is on their behalf that we are writing to you to ask you to change your Brexit approach".
Alliance deputy leader Stephen Farry said: "After well over 33 months being available to agree and ratify the terms for Brexit, it is simply stunning, reckless and irresponsible that no formal way forward has been agreed with barely over nine days to go".
And that is what I am determined to do.