Top UK minister Amber Rudd quits, dealing Boris Johnson new Brexit blow

British minister Amber Rudd has quit the Conservatives and her post as work and pensions secretary, saying she can't stand by as colleagues are expelled.

British minister Amber Rudd has quit the Conservatives and her post as work and pensions secretary, saying she can't stand by as colleagues are expelled. Source: AP

Senior British minister Amber Rudd has sensationally quit the cabinet and the Conservative Party in protest at Boris Johnson's handling of Brexit.

Ms Rudd has quit her post as work and pensions secretary and said she was relinquishing the Tory whip after the prime minister sacked 21 rebels this week.

Amber Rudd (flanked by Prime Minister Boris Johnson) sensationally quit Mr Johnson’s cabinet over the Brexit saga. Source: EPA

Mr Johnson removed the whip from two former chancellors and Winston Churchill's grandson after they voted to give opposition MPs control of the order paper and start the process of blocking a no-deal Brexit.

"I cannot stand by as good, loyal moderate Conservatives are expelled," she declared on Saturday.

"I have spoken to the PM and my Association Chairman to explain. I remain committed to the One Nation values that drew me into politics."

Ms Rudd said she thought a no-deal Brexit was now the government's main aim.

The former home secretary was dogged by questions throughout the Tory leadership contest about whether she could serve in Mr Johnson's cabinet if he won the race.

She accepted the offer of continuing in her job as work and pensions secretary when Johnson formed his cabinet in July.

Ms Rudd said she "no longer believed leaving with a deal is the government's main objective". Source: EPA

However, in her letter of resignation, the now independent MP said that while she accepted the need to keep a no-deal Brexit as an option, she "no longer believed leaving with a deal is the government's main objective".

Issuing forthright criticism of Mr Johnson, she called his decision to sack Tory rebels - such as ex-chancellor Philip Hammond, Churchill's grandson Nicholas Soames and Ken Clarke, the longest-serving MP in the House of Commons - "an assault on decency and democracy".

Britain's Prime Minister Boris Johnson. Source: Getty Images Europe

"This short-sighted culling of my colleagues has stripped the party of broad-minded and dedicated Conservative MPs. I cannot support this act of political vandalism," Ms Rudd said.

"Therefore, it is with regret that I am also surrendering the Conservative whip."

Labour says Ms Rudd's sudden resignation was a sign that no one trusts the PM. Source: EPA

Labour Party chair Ian Lavery said Ms Rudd's sudden resignation was a sign that no one trusts the PM.

"The prime minister has run out of authority in record time and his Brexit plan has been exposed as a sham," he said.

"No one trusts Boris Johnson. Not his cabinet, not his MPs, not even his own brother.

"After nine years of austerity, we need a Labour government that will invest in our communities and public services."