Philip Hammond has insisted the government has "no red lines" on Brexit as crisis talks between the Conservatives and Labour continue.

The chancellor suggested everything was on the table during discussions with Jeremy Corbyn's team and said he was "optimistic" of an agreement being reached.

His comments appear to contradict those of Theresa May, who has repeatedly insisted that any Brexit deal must meet a number of conditions, including ending freedom of movement and allowing the UK to make independent trade deals. She has also consistently ruled out a fresh referendum on any deal approved by parliament, which is Labour Party policy.

Negotiating teams consisting of ministers and shadow ministers held talks on Thursday and Friday in a bid to find a cross-party solution to the deadlock in parliament.

But Labour claimed that ministers' refusal to change the wording of the political declaration on the future UK-EU relationship had hindered progress.

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(AP Photo/ Kirsty Wigglesworth) Kirsty Wigglesworth AP Opposing protesters flock to parliament on would be date of Brexit A pro-Brexit protester holds a sign next to a statue of Winston Churchill at the March to Leave demonstration in London, Britain March 29, 2019. REUTERS/Toby Melville TOBY MELVILLE Reuters Opposing protesters flock to parliament on would be date of Brexit Brexit demonstrators in Parliament Square in Westminster, London. PRESS ASSOCIATION Photo. Picture date: Friday March 29, 2019. See PA story POLITICS Brexit. Photo credit should read: Jonathan Brady/PA Wire Jonathan Brady PA Opposing protesters flock to parliament on would be date of Brexit Pro-Brexit protesters hold signs and wave flags at the March to Leave demonstration in London, Britain March 29, 2019. 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Sir Keir Starmer, the shadow Brexit secretary, said the government "isn't proposing any changes to the deal...in particular, it's not countenancing any changes to the actual wording of the political declaration".

Downing Street, however, insisted the government was "prepared to pursue changes to the political declaration to deliver a deal that is acceptable to both sides".

Mr Hammond also said the government was not ruling anything out, despite staunch opposition from many Conservative MPs and ministers to any prospect of a fresh referendum or the UK remaining in a customs union with the EU.

He said: "We should be open to listen to suggestions that others have made. Some people in the Labour Party are making other suggestions to us; of course we have to be prepared to discuss them.

"Our approach to these discussions with Labour is that we have no red lines, we will go into these talks with an open mind and discuss everything with them in a constructive fashion."

Ms May will travel to Brussels on Wednesday to request a further extension to the Article 50 period with the two sides split over the length of the possible delay. The EU is expected to propose a one-year extension, while the prime minister wants to delay Brexit only until 30 June.

Unless every EU member state approves the request for a further delay, the UK will leave the bloc without a deal on 12 April.

But Mr Hammond said he was confident the extension would be signed off at the meeting of the European Council.

He said: "Most of the colleagues that I am talking to accept we will need longer to complete this process.

"I am optimistic about the Council on Wednesday."

On Saturday, Labour's shadow home secretary, Diane Abbott, said the government needed to show "more flexibility than it has done so far".