The EU's chief Brexit negotiator Michel Barnier has said he's "not optimistic" about avoiding a no-deal Brexit.
He has written an article in the Sunday Telegraph newspaper suggesting the Irish backstop is the "maximum amount of flexibility that the EU can offer to a non-member state".
British Prime Minister Boris Johnson has repeatedly insisted the backstop - an 'insurance policy' aimed at avoiding a hard border in Ireland - must be dropped in any Brexit deal.
That demand has been rejected by the EU, who've said no credible alternatives have been put forward by the UK.
In his Telegraph article, Mr Barnier argued: "On the EU side, we had intense discussions with EU member states on the need to guarantee the integrity of the EU's single market, while keeping that [Irish] border fully open.
"In this sense, the backstop is the maximum amount of flexibility that the EU can offer to a non-member state."
He added: "I am not optimistic about avoiding a no-deal scenario, but we should all continue to work with determination.
"The EU is ready to explore all avenues that the UK government may present and that are compatible with the withdrawal agreement."
Gove comments
Today, the British government has faced fresh criticism after a senior minister refused to say whether they'd abide by any law approved by MPs to delay Brexit.
Michael Gove was speaking on the Andrew Marr Show on BBC.
Opposition MPs and Tory rebels are expected to intensify efforts to introduce legislation opposing no-deal this week, ahead of the expected suspension of parliament for more than a month.
Labour's Keir Starmer confirmed the plan is to bring forward legislation to prevent the government "from taking us out of the EU without a deal" - but offered no details on the specifics.
Mr Gove - who's in charge of no-deal planning - refused to be drawn on whether Boris Johnson's administration would abide by any legislation passed to delay Brexit.
He suggested: "You're asking me about a big in a poke - I will wait to see what legislation the opposition may try to bring forward."
Would the government abide by a new law from MPs to delay #Brexit? #marr asks the Chancellor of the Duchy of Lancaster Michael Gove https://t.co/4yDchmzhSs pic.twitter.com/fA2b7Ci3e0
— BBC Politics (@BBCPolitics) September 1, 2019
Labour shadow chancellor swiftly condemned the comments, claiming it was a "startling move beyond anything we've ever seen".
The Tory attack on our democracy is getting worse. Gove has just refused to confirm to @AndrewMarr9 that the government will accept legislation passed by Parliament. This is a startling move beyond anything we’ve ever seen. Johnson government is becoming an elective dictatorship.
— John McDonnell MP (@johnmcdonnellMP) September 1, 2019
It comes as Boris Johnson continued to call on Conservative MPs to back his Brexit approach.
A number of Tory rebels have indicated they'll back efforts to block a no-deal scenario.
In an interview with The Sunday Times, Mr Johnson argued: “I just say to everybody in the country, including everyone in parliament, the fundamental choice is this: are you going to side with Jeremy Corbyn and those who want to cancel the referendum?
"Are you going to side with those who want to scrub the democratic verdict of the people - and plunge this country into chaos?"
“Or are you going to side with those of us who want to get on, deliver on the mandate of the people and focus with absolute, laser-like precision on the domestic agenda? That’s the choice.”
Meanwhile, Labour leader Jeremy Corbyn reiterated that his party will do "everything possible" to stop a no-deal Brexit.
In an article for The Observer, Mr Corbyn suggested: "This week could be the last chance to stop Johnson’s Tory government taking us over a no-deal cliff edge that will threaten jobs and our NHS, mean a restoration of the border in Ireland – threatening peace – and cause shortages of food and medical supplies from day one."
