LONDON 

The British prime minister on Thursday defended the emergency Rwanda Bill as the "toughest anti-illegal immigration law ever” and pledged to "not allow a foreign court to block" Rwandan flights.

Rishi Sunak made a speech on illegal migration at a news conference in London and said the bill will deliver an "effective deterrent" to those who wish to come to the UK illegally and it will restore people’s trust that the system is fair and "ultimately -- to stop the boats."

"And so, our Bill today fundamentally addresses the Supreme Court’s concerns over the safety of Rwanda. I did not agree with their judgment, but I respect it," he said.

Early this week, the UK signed a new treaty with Rwanda to address the concerns of the UK Supreme Court, which last month ruled that the government's original plan to send asylum seekers to the East African country was unlawful.

The new treaty seeks to ensure that those who are relocated to Rwanda under the partnership are not at risk of being returned to a country where their lives or freedoms would be threatened -- an act known as refoulement, according to the Home Office.

Sunak said the bill also ends "the merry-go-round of legal challenges" that blocked the government's policy, stressing that they simply cannot have a situation where the government's ability to control our borders and stop people taking perilous journeys across the channel "is held up in endless litigation in our courts."

"So this Bill gives parliament the chance to put Rwanda’s safety beyond question in the eyes of this country’s law. Parliament is sovereign. It should be able to make decisions that cannot be undone in the courts," he said.

Elaborating, the British premier underlined that UK domestic courts will no longer be able to use any domestic or international law, including the Human Rights Act, to stop the government from removing illegal migrants.

"That means that this Bill blocks every single reason that has ever been used to prevent flights to Rwanda from taking off," he said.

- 'I will not allow a foreign court to block these flights'

Once migrants have been removed, they will also be banned for life from traveling to the UK, settling here, or becoming a citizen, he said.

But Sunak stated that they could still face challenges from the European Court of Human Rights in Strasbourg even with the new initiative.

"I will not allow a foreign court to block these flights. If the Strasbourg Court chooses to intervene against the express wishes of our sovereign parliament. I will do what is necessary to get flights off," he said.

Defending his government's immigration policy, Sunak said the Rwanda policy is only one part of a wider strategy to stop the boats. "And that strategy is working,” he said.

"We will get flights off the ground, we will deter illegal migrants from coming here, and we will, finally, stop the boats," he added.

Meanwhile, the government's immigration policy is under fire, as Immigration Minister Robert Jenrick stepped down Wednesday because of the government's Rwanda plan.

Former Home Secretary Suella Braverman who was sacked last month, said the Rwanda Bill "won't work."

During this week's Prime Minister's Questions (PMQ) session in parliament, main opposition Labour Party Leader Keir Starmer called the plan a "gimmick" and said the Tories "have broken the asylum system."

The Rwanda plan had been one of the most controversial planks of the government's migration policy, as it sparked international criticism and mass protests across the UK.

Tackling small boat crossings by irregular migrants across the British Channel is among five priorities of the government, as more than 45,000 migrants arrived in the UK that way last year.