Campaigners have called on the UK Government to completely abandon sending migrants to Rwanda after judges ruled the plan was lawful.

Several challenges were brought against the proposals announced by then-home secretary Priti Patel in April, which she described as a “world-first agreement” with the east African nation in a bid to deter migrants from crossing the Channel.

The first deportation flight – due to take off on June 14 – was then grounded amid a series of objections against individual removals and the policy as a whole.

However, at the High Court on Monday, senior judges rejected arguments that the plans to provide one-way tickets to Rwanda were unlawful.

Lord Justice Lewis, sitting with Mr Justice Swift, dismissed the challenges against the policy as a whole, but ruled in favour of eight asylum seekers, finding the UK Government had acted wrongly in their individual cases.

In a summary of the ruling, Lord Justice Lewis said: “The court has concluded that it is lawful for the Government to make arrangements for relocating asylum seekers to Rwanda and for their asylum claims to be determined in Rwanda rather than in the United Kingdom.”

Opposition politicians, charities and other organisations lined up to condemn the multimillion-pound deal, arguing it will “do nothing” to stop Channel crossings.

Labour’s shadow home secretary Yvette Cooper branded the plan “unworkable”, “unethical” and “extortionately expensive”, adding that it was a “damaging distraction from the urgent action the Government should be taking to go after the criminal gangs and sort out the asylum system”.

SNP home affairs spokesperson, Alison Thewliss, said: “Whether legal or not, this move is deeply immoral and will only serve to endanger those the UK Government has a duty to protect.

“Those fleeing war, famine and oppression deserve and need our full support, instead the Tories have chosen to make scapegoats of desperate people in a disgusting attempt to cover up their own domestic policy failings.

“Countries like the UK should act as a beacon of hope and serve as a positive example to the rest of the world."

But Ms Braverman said she is “committed” to making the plan to send migrants to Rwanda work.

The Home Secretary said she has “always maintained that this policy is lawful".

She added: “Our ground-breaking migration partnership with Rwanda will provide individuals relocated with support to build new lives there, while disrupting the business model of people-smuggling gangs putting lives at risk through dangerous and illegal small boat crossings.

“I am committed to making this partnership work – my focus remains on moving ahead with the policy as soon as possible and we stand ready to defend against any further legal challenge,”

Amnesty International UK said the Rwanda plan should be “abandoned in its entirety” and called on Home Secretary Suella Braverman to “stop playing politics with people’s lives and get down to the serious task of fixing the disastrously dysfunctional asylum system and policies that she recklessly adopted from her predecessor”.

Amnesty's refugee and migrant rights director, Steve Valdez-Symonds, said the charity “remains gravely concerned that the Government’s Rwanda deal profoundly undermines international refugee law and rides roughshod over the rights of people seeking asylum in the UK”.

He added: “Transporting people thousands of miles away to Rwanda – a country with its own asylum and human rights challenges – is expensive, unjust and deeply cruel.”

Christina Marriott, British Red Cross director of policy, said the “offshoring of human beings should play no part in our asylum system. It will do little to prevent people from risking their lives to reach safety”, and urged the Government instead to focus on establishing safe and legal routes for asylum seekers.

Freedom from Torture’s policy advocacy director Steve Crawshaw described the ruling as “deeply troubling” and said the policy was “terrible”.

Sending migrants to Rwanda is “immoral, ineffective and incredibly costly for taxpayers”, the Liberal Democrats said, warning it will “do nothing to stop the dangerous Channel crossings or combat people smuggling and human trafficking; instead it will give criminal gangs more power and profits”.

Enver Solomon, chief executive of the Refugee Council, said the plans will “damage the UK’s reputation as a country that values human rights”, adding: “Treating people who are in search of safety like human cargo and shipping them off to another country is a cruel policy that will cause great human suffering.”