EU leaders are set to decide on Friday whether to grant the UK a three-month Brexit extension, the BBC’s Europe editor Katya Adler says.
Most EU nations back it but France “is digging its heels in”, she adds.
So there could be an emergency summit in Brussels on Monday to allow leaders to reach agreement face-to-face.
Boris Johnson insists the UK will leave the EU next week with or without a deal and he will seek a snap election if the EU grants an extension to January.
The prime minister was forced to send a letter to the EU requesting an extension, under legislation passed by MPs last month.
But he said he had told EU leaders his policy was still to leave on 31 October.
Commons Leader Jacob Rees-Mogg told MPs the government “does not want an extension” and was “making every preparation to leave on 31 October”.
Dominic Cummings, Mr Johnson’s chief adviser, is reported to be urging ministers to abandon attempts to get the prime minister’s Brexit deal through Parliament and go for a December election instead.
But some ministers – such as Northern Ireland Secretary Julian Smith – are understood to be urging the prime minister to make another attempt to get his deal through Parliament first.
Cabinet ministers are meeting and are expected to discuss the way forward.
French President Emmanuel Macron is concerned that a long extension could lead to more UK indecisiveness or an inconclusive general election, the BBC understands.
But if the EU approves the UK’s request for a three-month extension, Mr Johnson would have to accept it, under the terms of the so-called Benn Act.
He would also have to accept any alternative duration suggested by EU leaders, unless MPs decide not to agree with it within two days.
Neither a motion for an early election nor another attempt to get the Brexit deal through has so far been scheduled for next week’s business in Parliament.
President Macron favours a short, sharp Brexit delay, encouraging MPs and the UK government to concentrate on ratifying the newly negotiated Brexit deal.
Mr Macron is fed up with the more-than-three-year EU focus on Brexit and the ever-present threat of a no-deal scenario.
He would rather shift attention to reforming the EU itself, to the benefit (he believes) of the countries remaining in it.
Of course, the French president knows Brexit won’t be over if and when the UK leaves.
Brexit Chapter Two – the negotiations on a comprehensive EU-UK trade deal – will likely be lengthy and complex, but they will largely be the competence of the European Commission, landing far more rarely on EU leaders’ in-trays.
If Mr Johnson had got his way in a Commons vote on Tuesday, MPs would now be debating the Withdrawal Agreement Bill, which would put his Brexit deal into law.
Instead, they are debating the Queen’s Speech, the government’s proposed programme for the next session of Parliament, if there is not an early general election.
MPs are due to vote at about 17:00 BST on whether to approve the Queen’s Speech, a formality when the government has a majority, but the result is expected to be close.
Shadow chancellor John McDonnell said Labour was ready for a general election “whenever it comes”, but he refused to be drawn on whether his party would back one if Mr Johnson held a vote on it next week.
“We will see what happens. We are trying to take this in stages,” he said.