Britain's hardline former interior minister Suella Braverman on Wednesday issued Conservative Prime Minister Rishi Sunak an ultimatum to get tougher on immigration or face certain wipeout at the polls.
Braverman -- sacked last month after a series of outspoken comments -- told parliament it was "now or never" to tackle "mass, uncontrolled, illegal immigration".
Migration to the UK -- long a vexed and emotionally charged political issue in the country -- is already taking centre stage in a general election widely expected next year.
Braverman has become the cheerleader of the vocal right-wing of the Conservative party and is thought to be positioning herself as a future leader if Sunak is forced to quit after the nationwide vote.
Her statement comes just a day after her successor as home secretary, James Cleverly, signed a new treaty with Rwanda that Sunak hopes will see thousands of migrants deported to cut record immigration levels.
Braverman, a former attorney general, has called for tougher measures before, and criticised the UN convention on refugees and European human rights legislation for blocking the government's plans.
But her latest comments go further, and will be red meat to fellow right-wing Tories who see having total control over Britain's borders as the final piece in the Brexit jigsaw.
"The Conservative party faces electoral oblivion in a matter of months if it introduces yet another bill destined to fail," Braverman told MPs, referring to expected emergency legislation over Rwanda.
The Tories faced a stark choice to "fight for sovereignty or let our party die", she said, adding: "I refuse to sit by and allow us to fail."
"We are running out of time," she warned.
Sunak, she said, needs "political courage" to go further than his existing plans, which were formulated after Supreme Court judges deemed the deportation policy illegal under international law.
She called for any new bill to address the court's concerns about the safety of Rwanda to allow flights before the election expected next year, by "blocking off all routes of challenge".
"The powers to detain and remove (migrants) must be exercisable notwithstanding the Human Rights Act, the European Convention on Human Rights, the Refugee Convention, and all other international law," she said.
Braverman called for removals to happen within days of arrivals, and for the "administrative detention of illegal arrivals until they are removed".
"If the prime minister leads that fight he has my total support," she said, indicating that Sunak will face damaging in-fighting if he does not.
The first deportees were due to be sent to Rwanda in June last year but were pulled off a flight at the last minute after a judge at the European Court of Human Rights issued an injunction.
Since then, their cases -- and the wider legality of the policy -- have been stuck in the courts, hampering Sunak's pledge to "stop the boats".
Almost 30,000 irregular migrants have crossed the channel from northern France in rudimentary vessels this year.
But Braverman said: "Many are not refugees but economic migrants, all have paid thousands of pounds to criminal gangs to break into Britain.
"They have come from a safe country -- France -- which, let's face it, should be doing much more."
The government hopes its new treaty will get migrants on planes by the spring but legal experts have questioned whether it will allay judges' concerns that Rwanda is not a safe third country.
Record levels of regular migration are also posing a headache for Sunak, with data released last month showing that 745,000 more people arrived in Britain last year than left.
Cleverly unveiled several measures on Monday that he said would result in 300,000 fewer people coming to the UK in the coming years.
Critics said the decision to prevent overseas health and social care staff from bringing dependents to Britain would split up families.