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Philip Hammond is plotting with Labour to stop Boris Johnson delivering a no-deal Brexit.

The ex-chancellor reportedly held a private meeting with Shadow Brexit Secretary Sir Keir Starmer on Wednesday.

Hammond is a vocal opponent of a no-deal exit and has said he will do all he can to stop it.

He resigned as chancellor on Wednesday before Johnson officially became prime minister.

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Philip Hammond is reportedly plotting with the Labour Party and other Members of Parliament opposed to a no-deal Brexit to stop Boris Johnson taking the United Kingdom out of the European without a deal.

Hammond - who quit his former role as chancellor before Johnson became prime minister - held a meeting with Labour's Shadow Brexit Secretary Sir Keir Starmer in Parliament on Wednesday, The Observer reports.

The report adds that Hammond and Starmer agreed to work together and with other senior MPs opposed to a no-deal exit, like Conservatives Oliver Letwin and Dominic Grieve, in finding ways to stop it happening in October.

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Prime Minister Johnson has made leaving the EU on October 31 the core pledge of his premiership, even if it means doing so without a deal. During his leadership campaign, he described it as "do or die."

He told MPs this week that if the EU doesn't agree to remove the Northern Irish backstop from the Withdrawal Agreement, then he would abandon the deal negotiated by Theresa May, and leave without an agreement.

Michel Barnier, the EU's chief Brexit negotiator, described removing the backstop as "unacceptable."

This week Johnson appointed Conservative MPs to senior positions of his Cabinet who strongly advocate leaving the EU without a deal if necessary. They include Home Secretary Priti Patel and Foreign Secretary Dominic Raab.

Michael Gove, who Johnson chose to oversee no-deal preparations, wrote in the Sunday Times newspaper that the government was "working on the assumption" of the UK leaving without a deal on Halloween.

Hammond has been a vocal opponent of a no-deal Brexit, particularly in his final weeks as Theresa May's chancellor.

During the Conservative leadership campaign, he warned Johnson and his rival Jeremy Hunt that a no-deal Brexit would leave them with no money to fulfill the various spending promised they had made.

The Office for Budget Responsibility (OBR) - which provides the government with independent economic analysis - warned earlier this month that a no-deal Brexit would likely push the UK into recession next year.

The OBR said that leaving the EU without a deal would cause UK economic growth to fall by two per cent by the end of 2020, and inflict a yearly £30 billion hit to public finances.

Hammond hinted on Tuesday that he could vote to bring down his own government in order to stop a no-deal Brexit.

"I would be wrong for the British government to seek to pursue no deal as a policy and I believe that it will be for the House of Commons, of which I will continue proudly to be a member, to ensure that that doesn't happen," he told MPs.

MPs on all sides of the House of Commons are engaged in ongoing discussions about how they can use legislation to stop Johnson forcing through a no-deal exit on October 31.

MPs involved in the discussions are set to initiate legislation in September once Parliament has returned from its summer recess. A former Conservative minister last week told Business Insider "we will find a way."

Earlier this month, a sizeable majority of 41 MPs voted to effectively prevent Johnson from suspending - or proroguing - Parliament in order to through a no-deal exit.

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