The Chancellor Philip Hammond announces he will resign live on TV

Philip Hammond has announced he will quit his cabinet position if Boris Johnson becomes Prime Minister.

Mr Hammond announced his intention to resign should Mr Johnson win the leadership race on the BBC's Andrew Marr Show on Sunday morning.

The Chancellor of the Exchequer has been in Number 11 Downing Street for three years and is a strong opponent to a no-deal Brexit.

Tory leadership contest favourite Boris Johnson has expressed his willingness to press forward with no deal if he cannot secure changes to the Withdrawal Agreement.

Philip Hammond, appearing on the BBC1 current affairs programme, The Andrew Marr Show. (PA)

Asked if he thought he would be sacked, Mr Hammond said: "No, I'm sure I'm not going to be sacked because I'm going to resign before we get to that point.

"Assuming that Boris Johnson becomes the next prime minister, I understand that his conditions for serving in his government would include accepting a no-deal exit on October 31, and it's not something that I could ever sign up to.

"It's very important that the Prime Minister is able to have a chancellor palace to tender her own resignation on Wednesday."

Mr Hammond is now the second cabinet minister to announce his intention to quit if Mr Johnson becomes Prime Minister.

Justice Secretary David Gauke - a former Remainer - told the Sunday Times he would also quit on Wednesday if Mr Johnson enters Number 10.

Mr Gauke said: "If the test of loyalty to stay in the Cabinet is a commitment to support no-deal on October 31 - which, to be fair to him, Boris has consistently said - then that's not something I'm prepared to sign up to.

"I recognise that this spell in Government is coming to an end. Given that I've been in the Cabinet since Theresa May came to power, I think the appropriate thing is for me to resign to her."

"I'm going to resign before we get to that point." (Jeff Overs/BBC via Getty Images)

Mr Hammond has been a prominent critic of the idea of a no-deal Brexit.

He recently indicated he may vote to bring down the next Prime Minister to stop it happening.

Conservative Party members are voting in a postal ballot to elect the next leader.

The 160,000 members must return their ballots by 5pm on Monday, with the winner expected to be announced on Tuesday.