Imminent March 29 Brexit cliff edge will be pushed back if MPs back Theresa May's deal

In a press conference confirming the decision in Brussels, Mr Tusk said confirmed the new dates, their conditions and said all options - including deal, no deal cancelling Brexit and a further extension - remain on the table.

Mr Tusk said he met British prime minister Theresa May "several times" on Thursday evening to be "sure" the deal details would be agreed.

And he was supported by Mr Juncker, who said the EU has worked "tirelessly" to secure the dates and that "this completes the whole package".

Asked how long a long extension may be, Mr Juncker said "until the very end".

In a separate question, Mr Tusk was asked about his recent comments at a previous EU summit where he said there is a "special place in hell" for people who promoted Brexit inaccurately, and if this special place should now be extended to MPs.

After pausing, Mr Tusk said "according to our pope, hell is still empty, so there is plenty of space" before Mr Juncker added "don't go to hell!".

An EU source later confirmed: "March 29 is over. April 12 is the new 29.”

Under the deal, Ms May will seek to have the withdrawal agreement passed by the House of Commons next week. Should it pass, the deadline would move back to May 22.

If it is defeated again, the deadline would move to April 12 - a date which is the final cut off point for Britain deciding if it runs candidates in the MEP elections.

If it chooses to run candidates in the MEP elections, Britain will be effectively dragged into a lengthy Brexit delay Ms May has previously insisted she would not accept.

The EU offer to Britain was hammered out after hours of chaotic and frantic talks among EU leaders on Thursday evening.

Leaders were locked in discussions for several hours over proposals to postpone Brexit, amid wrangling over the final deadline for the UK to leave.

Taoiseach Leo Varadkar and 26 other EU leaders spent the day struggling to resolve how to solve the Brexit riddle, with dates of April 11, April 12, May 7 and May 22 being offered up as a means of pulling Britain back from the brink.

Ms May had earlier told Mr Varadkar in a "short" bilateral meeting she wants to avoid a no deal crisis and that her deal would be passed through parliament by now if it wasn't for House of Commons speaker John Bercow's intervention third vote veto threat.

However, her claim was given little sympathy, with EU leaders forming a brick wall of criticism by saying her preferred June 30 delay date is impossible and that she must find a way to end the crisis.

French president Emmanuel Macron went further, warning Britain "in case of no, it will guide to a no deal. For sure. This is it. We are ready".

European Council president Donald Tusk and European Commission president Jean-Claude Juncker tried to give the same no deal cliff edge threat message while stressing the EU is still ready to work with Britain to find a solution.

However, noting Ms May's failure to rule out a no deal Brexit and her commitment to finding a "short" extension, Luxembourg prime minister Xavier Bettel said Brexit is "like Waiting for Godot".