Diplomats from the other EU member states have been told the UK will leave without a deal unless major changes are made to Theresa May’s agreement, but that proposals such as abolishing the Irish backstop were unacceptable.
One negotiator said: “We are back where we were three years ago.”
Downing Street said it hoped the EU would rethink its refusal of changes.
A spokesperson said the EU “needed to change its stance”, adding: “We will throw ourselves into the negotiations with the greatest energy and the spirit of friendship and we hope the EU will rethink its current refusal to make any changes to [Mrs May’s] Withdrawal Agreement.”
The plan negotiated between the EU and Mrs May was voted down by MPs three times.
New Prime Minister Boris Johnson has pledged to “do or die”, and leave the EU by the deadline of 31 October, with or without a deal.