The Conservative leader had said the scheme was crucial to reduce rising immigration, which is set to be a key battleground at the next general election expected in 2024.
The ruling is the latest episode in a long-running saga that began in April last year when the policy was signed under then-prime minister Boris Johnson.
Will change law, if needed: Sunak
Hours after the SC’s judgment, Sunak said his government was already working on a new treaty with Rwanda and could change the country’s laws.
“The government has already been working in advance on a new treaty with Rwanda, which we will finalise in light of today’s judgement,” Sunak told parliament.
“If it becomes clear that our domestic legal frameworks or international conventions are still frustrating plans at that point, I am prepared to change our laws and revisit those international relationships. The British people expect us to do whatever it takes to stop the boats,” he added, referring to asylum seekers arriving from France on small boats via the Channel.
Sunak dealt a massive blow
The SC’s decision leaves Sunak’s immigration plans in tatters — and could widen rifts in the ruling Tory party between right-wing lawmakers and moderates.
The Migration and Economic Development Partnership had envisaged sending to Rwanda anyone who had made what the government calls “dangerous or illegal journeys, such as by small boat or hidden lorries” to the UK.
More than 27,000 have made the journey this year.
Sunak made stopping the small boats one of his five key priorities after succeeding Liz Truss in October last year.
The first deportees were on a plane and ready to fly to Rwanda in June 2022 until a last-minute injunction from the European Court of Human Rights (ECHR). Nobody has been deported under the scheme so far.
Five justices on the country’s top court said on Wednesday that asylum-seekers would be “at real risk of ill-treatment” because they could be sent back to their home countries once they were in Rwanda.
More ammunition for Braverman
The SC’s decision may spark demands from right-wingers that Britain withdraw from the ECHR — a drastic idea that Sunak has so far refused to back.
Political observers expect those calls to be headed by outspoken former interior minister Suella Braverman — sacked by Sunak this week following a string of controversial comments.
Braverman, widely believed to covet the Tory leadership if Sunak quits after the election, has called sending asylum seekers to Rwanda her “dream” and “obsession”.
What is the Rwanda plan?
The Rwanda plan, struck in April 2022 by then Prime Minister Boris Johnson, is designed to deter asylum seekers from making the dangerous journey of about 20 miles (32 km) across the Channel from Europe in small boats or inflatable dinghies to England’s southern beaches.
Last year, a record 45,775 people were detected arriving without permission in Britain in this way. So far this year, more than 27,000 have arrived on small boats.
Under the scheme, anyone who arrived in Britain illegally after January 1 last year faced deportation to Rwanda, some 4,000 miles (6,400 km) away, where their claims would be assessed.
(With inputs from agencies)
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