THE government was branded “institutionally racist,” “cowardly” and “barbaric” yesterday over multimillion-pound plans for asylum-seekers who cross the Channel in small boats to be processed in Rwanda.

Prime Minister Boris Johnson admitted that he expects a court challenge to the proposals, contained in clause 28 of the Nationality and Borders Bill, to detain and fly migrants more than 4,000 miles on chartered planes to the east African country.

He said the Royal Navy would take over “operational command” from Border Force in the English Channel to ensure that “no boat makes it to the UK undetected.”

About 250 to 300 military personnel will be dedicated to police migrants on busy days, working on ships and aircraft in the English Channel.

An initial £120 million is expected to be paid to the Rwandan government under an economic deal, with Home Secretary Priti Patel striking an agreement during a visit to the capital Kigali.

She said that the “vast majority” of those who arrive in Britain “illegally” will be detained and considered for relocation to Rwanda but declined to share specific details.

The number of people who can be relocated will be “unlimited,” with the first due to receive formal notifications within weeks and the first flights expected to take place in the coming months.

Mr Johnson pledged £50 million in new funding for boats, aerial surveillance and military personnel to help ensure that the measures are a “very considerable deterrent” to crossings.

He said the individuals who succeed in reaching Britain “will be taken not to hotels at vast public expense” but to Greek-style detention centres, the first of which will open “shortly.”

Human rights groups warned that similar practices in Australia had led to “rampant abuses” in camps, including rape, murder and suicide.

They called on the government to treat refugees with dignity and compassion by creating more safe routes to claim asylum and dropping the Borders Bill.

Refugee Action chief executive Tim Naor Hilton said that the “grubby cash-for-people plan” would be a “cowardly, barbaric and inhumane way to treat people fleeing persecution and war.”

He added: “Our so-called ‘Global Britain’ is offshoring its responsibilities onto Europe’s former colonies instead of doing our fair share to help some of the most vulnerable people on the planet.”

Freedom from Torture chief executive Sonya Sceats said that the plans were “deeply disturbing and should horrify anybody with a conscience.”

She said: “It is even more dismaying that the UK government has agreed this deal with a state known to practice torture, as we know from the many Rwandan torture survivors we have treated over the years.”

Steve Valdez-Symonds of Amnesty International UK argued that the “ill-conceived” plans, which he said would  inflict further suffering while wasting huge amounts of public money, showed “how far removed from humanity the government is.”

He said: “After the chaos and bureaucracy-ridden failures of schemes the government clearly never truly wanted for Afghans and Ukrainians, this is a hugely misjudged distraction from the core work of creating a humane and properly functioning asylum system.”

Sophie McCann of Doctors without Borders (MSF) said the group had “witnessed some of the worst suffering” in Australia’s offshore camps on Nauru island.

She said: “Children as young as nine years old were trying to kill themselves.

“This kind of suffering is what awaits refugees in Rwanda.  It is medically and ethically reprehensible.”

She pointed out that the measures would deny refugees opportunities to gain a fair hearing and conceal their suffering from public view.

“Make no mistake, this government knows what the impact of this policy will be — it is knowingly and willingly subjecting refugees to horrific suffering,” she said.

Scottish Greens human rights spokeswoman Maggie Chapman said: “Even by the terrible standards of the institutionally racist Home Office, this would be a disgraceful new low.

“It is a repressive and authoritarian proposal that rejects the fundamental principle and right of asylum.”

Labour leader Sir Keir Starmer called the plans “unworkable,” “extortionate” and an attempt to distract from Mr Johnson being fined for breaching his own Covid-19 laws.

The deal with Rwanda comes after other locations touted, including Ascension Island, Albania and Gibraltar, were rejected, at times angrily, by the governments concerned.