Two senior British government ministers said they would quit before Boris Johnson became prime minister because of their profound differences over Brexit. Mr Johnson, the former foreign secretary, is the strong favourite to win a vote of 160,000 members of the ruling Conservative party that will decide the successor to Theresa May. The result will be announced on Tuesday and Mrs May will step down the following day, after failing to push her vision of Brexit through parliament. The anticipated victory of Mr Johnson – who has staked his reputation on Britain leaving the European Union on October 31 – will marginalise politicians such as Philip Hammond, the chancellor, who is implacably opposed to leaving without any agreement in place on the future trading and political relationship with the 28-nation bloc. Mr Hammond and David Gauke, the Justice Secretary, both said they would resign to Mrs May in the event of a Johnson victory. Mr Johnson is hoping to secure more than 60 per cent of the votes in the leadership election against Jeremy Hunt, the foreign secretary, according to reports on Sunday. "I'm sure I'm not going to be sacked because I'm going to resign before we get to that point," Mr Hammond told the <em>BBC</em>. He said that a no-deal Brexit, which would see the UK sever at a stroke all trading and regulatory agreements built up over 46 years, was not something that he could sign up to. Mr Johnson believes he can persuade the European Union to rewrite a deal agreed with Mrs May that his supporters say retained too much power for the bloc over the UK’s future. Mr Johnson has also said that he expected his party’s parliamentary members to accept the option of a “no-deal Brexit” if they wanted to join his cabinet if he becomes prime minister on Wednesday. “It's very important that the prime minister is able to have a chancellor who is closely aligned with him in terms of policy, and I therefore intend to resign to Theresa May before she goes to tender her own resignation on Wednesday,” said Mr Hammond. Mr Hammond's views meant he was never expected to be part of a Johnson administration. He had said that as a backbench MP, he would seek to scupper any plans to leave without a deal. Mr Gauke, who like Mr Hammond had campaigned to remain in the EU before the 2016 referendum, told <em>The Sunday Times </em>that Britain would face "humiliation" if it failed to secure an agreement with the EU before leaving. Even if the UK left without a deal in place, it would have to strike some sort of agreement in the future – but from a weaker position. “I fear that, frankly, there is a humiliation for us there if we go down that route,” the minister told the newspaper. Defence Minister, Tobias Ellwood, also on Sunday repeatedly declined to say if he would serve in a government led by Mr Johnson. With a slim majority for the ruling Conservative Party and the prospect of a rebellion from within its ranks, Mr Johnson faces difficulty in securing his Brexit deal through parliament. If his attempt ended in failure, it could lead to national elections to try to break the deadlock.