BRITAIN has set a “worrying precedent for dismantling” asylum obligations around the world, the UN refugee agency said after Parliament passed the Illegal Migration Bill today.

In a scathing response, the UN High Commissioner for Refugees warned the government legislation “will have profound consequences for people in need of international protection” and “other countries, including in Europe, may be tempted to follow.”

The government’s controversial plans to stop small boat crossings on the Channel will prevent people — including unaccompanied children — from claiming asylum in the UK if they arrive through unauthorised means.

Ministers also say the changes will ensure detained people are promptly removed, either to their home country or a third country such as Rwanda, though this is currently the subject of a legal challenge.

Campaigners said the Bill passing marked a “bleak day for human rights” that leaves the “vast majority” unable to claim asylum in the UK.

And in a joint statement UN High Commissioner for Human Rights Volker Turk and UN High Commissioner for Refugees Filippo Grandi warned the Bill is “at variance with the country’s obligations under international human rights and refugee law.”

It “extinguishes access to asylum in the UK for anyone who arrives irregularly,” barring “them from presenting refugee protection or other human rights claims, no matter how compelling their circumstances.”

They also warned it “creates sweeping new detention powers, with limited judicial oversight” with thousands now expected to remain in Britain indefinitely in precarious legal situations exposed to a greater risk of exploitation and abuse due to its lack of “viable removal arrangements with third countries.”

Mr Turk added: “In addition to raising very serious legal concerns from the international perspective, this Bill sets a worrying precedent for dismantling asylum-related obligations that other countries, including in Europe, may be tempted to follow, with a potentially adverse effect on the international refugee and human rights protection system as a whole.”

Mr Grandi said making the existing asylum system work more effectively was key to reducing the number of migrants crossing the Channel, but this will be “significantly undermined” by the new legislation.

Anti-racist protesters held a rally as an accomodation barge arrived at the port where it will house 500 asylum-seekers just hours after the government defeated challenges –  including pleas for modern slavery protections and child detention limits – to the Bill by peers.

Bibby Stockholm’s arrival into Dorset’s Portland Port marked a poignant ending to the parliamentary tussle over the reforms, paving the way for the Bill to receive royal assent.

A spokesman for Stand Up To Racism Dorset said it “is proud to have called a protest at Portland Port as the Bibby Stockholm barge was due to arrive.

“The event called for an 11th-hour intervention to halt the plan to house refugees on the barge. The only plans in place from the Home Office and Portland Port Ltd are inhumane and inadequately resourced for both refugees and local people.”

Sacha Deshmukh, Amnesty International UK’s chief executive, said: “Today is an extremely bleak day for human rights in this country.

“The Bibby Stockholm’s arrival at Portland comes on the same day as the new immigration law is set to shatter respect for the rights of refugees and victims of human trafficking in the UK’s asylum system.

“Disqualifying people’s asylum claims en masse regardless of the strength of their case is a blatant assault on international law and is a failure of UK leadership.

“We need a total rethink on asylum. The use of barges, former military sites and other completely unsuitable places of accommodation should end, this terrible new law and the Rwanda deal should be scrapped, and there should be a renewed focus on properly resourced decision-making and the creation of safe and legal asylum routes.”

Ministers had urged the Lords to allow the Bill to become law after signalling no further concessions were planned and MPs again overturned a raft of revisions previously made by the upper chamber.

Home Office minister Lord Murray of Blidworth said the number of small boat arrivals had “overwhelmed” the UK’s asylum system and was costing taxpayers £6 million a day to provide accommodation.