The United Kingdom's plan to send some asylum-seekers who arrive in the country to Rwanda as a part of a deal between the British government and the African country, has drawn criticism from opposition politicians and refugee groups, which they describe as "unworkable and inhumane."

Prime Minister Boris Johnson said Thursday people who seek to "abuse" Britain's immigration system will be removed to a third country or their country of origin.

"We must ensure that the only route to asylum in the U.K. is a safe and legal one and that those who tried to jump the queue or abuse our systems will find no automatic path to set them up in our country, but rather be swiftly and humanely removed to a safe third country or their country of origin," Johnson said while announcing the government's new immigration arrangement with Rwanda.

The risk of ending up in Rwanda rather than the U.K. will be a "considerable deterrent" over time, Johnson added.

Johnson also announced extra funds for boats, aircraft and surveillance equipment to patrol the Channel and detain people-smugglers. "This will send a clear message to those piloting the boats. If you risk other people's lives in the Channel, you risk spending your own life in prison," he said.

Media reports say the government plan would see some single men who arrive in Britain from across the English Channel in small boats flown 4,000 miles (6,400 kilometers) to Rwanda while their asylum claims are processed.

Simon Hart, the government minister for Wales, said the arrangement would cost Britain about 120 million pounds ($158 million). He said the goal was to "break up" the business model of criminal people-smuggling gangs.

"(If) we have an arrangement with the Rwandan government for the proper and humane treatment of these people, then the criminal gangs will realize that their potential source of income will dry up," Hart said.

Steve Valdez-Symonds, refugee director at Amnesty International U.K., said the government’s "shockingly ill-conceived idea will go far further in inflicting suffering while wasting huge amounts of public money." He said Rwanda’s "dismal" human rights record made the idea even worse.

The chief executive of the U.K.-based organization Refugee Council, Enver Solomon, called it a "cruel and nasty decision" and predicted it would not stop people-smuggling gangs.

Migrants have long used northern France as a launching point to reach Britain, either by stowing away in trucks or on ferries, or – increasingly since the coronavirus pandemic shut down other routes in 2020 – in dinghies and other small boats typically organized by smugglers.

More than 28,000 people entered the U.K. on small boats last year, up from 8,500 in 2020 and just 300 in 2018. Dozens have died, including 27 people in the November capsizing of a single boat.

The British and French governments have worked for years to stop the cross-Channel journeys, without much success, often swapping accusations about who is to blame for the failure. Last year, the U.K. agreed to give France 54 million pounds ($74 million) to help fund a doubling of the number of police patrolling French beaches.

Britain’s Conservative government has floated other proposals, including building a wave machine in the Channel to drive boats back and sending migrants to third countries. Several suggested locations – including Ascension Island, Albania and Gibraltar – were rejected, at times angrily by the nations suggested.

Opposition politicians accuse the government of trying to distract attention from a scandal over government parties that breached pandemic lockdown rules. Johnson was among dozens of people fined by police over the parties, making him the first British leader ever found to have broken the law while in office.

He is resisting calls from opponents, and some in his own party, to resign.

Labour Party lawmaker Lucy Powell said the Rwanda plan might please some Conservative supporters "and would certainly grab the headlines because it’s very controversial and contestable. But in reality, it is unworkable, expensive, and unethical."

"I think this is less about dealing with small boats and more about dealing with the prime minister’s own sinking boat," Powell told the BBC.