European Commission President Jean-Claude Juncker has warned that the UK must back Theresa May's withdrawal agreement by Friday next week to secure another short extension to Brexit.
Speaking in Brussels, he said: "If the UK is in a position of approving the Withdrawal deal with a viable majority by April 12 then the... European Union would also accept an extension until May 22.
"April 12 is the final date for possible approval. If the House of Commons does not adopt a stance before that date no short-term extension will be possible."
Mr Juncker added that a no-deal Brexit on April 12 was becoming "more and more likely".
His comments came as Mrs May was preparing to hold talks with Jeremy Corbyn in a bid to break the deadlock over Brexit.
The Prime Minister said on Tuesday she would seek "as short as possible" a delay to the current Brexit date of April 12, having repeatedly said she did not want Britain to have to take part in European Parliament elections on May 23.
Mr Juncker told the European Council: "The European Council has given all necessary time and space to the UK to take its decision. I believe a no-deal on April 12 at midnight has become a scenario which looks more and more likely.
"It's not what I want but we have made sure that the EU is ready to face up to that situation. We've been preparing since December 2017. We've always known that the logic of Article 50 makes no-deal a default option."
Mr Juncker also warned that the UK would be more affected than the EU in the event Britain crashes out of the bloc.
He said: "The measures that we have taken are temporary in nature, they are unilateral, they will protect the key interests of the union at least until the end of the year but the disturbances suffered by citizens (and) businesses in almost all sectors will be unavoidable.
"The UK will be more affected than the EU because a managed or negotiated no-deal does not exist any more so than a transition period for a no-deal."
Mrs May was hit today by the resignation of a Leave-backing minister over her decision to hold talks with Mr Corbyn.
Wales minister and whip Nigel Adams said the Prime Minister had made a "grave error" by reaching out to the Labour leader in the hope of finding a consensus solution to Brexit ahead of a crunch EU summit on April 10.
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