Priti Patel’s reported plans to hold asylum seekers in offshore processing centres have been branded “cruel”, “inhumane” and “dangerous”.
The home secretary will introduce new laws next week to allow the government to send asylum seekers abroad for processing, according to The Times.
The proposals would see the UK enter a joint enterprise with Denmark to hold asylum seekers in a centre in Rwanda.
The Home Office wants to emulate the policy used by Australia in processing asylum seekers offshore, after more than 5,600 migrants have crossed the Channel from France to England this year.
Watch: Priti Patel vows reform of 'broken' immigration system
The Times said Boris Johnson is keen on the plan, which would come under the Nationality and Borders Bill.
The newspaper said Home Office ministers have had discussions with their counterparts in Denmark, where a law to process asylum seekers outside Europe was passed earlier this month.
The UK is also reportedly following the lead of Australia, which bans asylum seekers travelling by sea and sends them to offshore centres in Papua New Guinea.
A government source, who The Times said is working on the plans, told the newspaper: “The prime minister and home secretary are determined to look at anything that will make a difference on Channel crossings.”
But the plans were met with fierce anger by campaigners and opposition politicians.
The Refugee Council said: “Offshore processing is an act of cruel and brutal hostility towards vulnerable people who through no fault of their own have had to flee war, oppression and terror.”
Labour Party MP Bell Ribeiro-Addy tweeted: “The government's plans to transport asylum seekers for offshore detention are impractical and inhumane.
“We should be doing all we can to help people rebuild their lives as part of our communities, not subjecting them to further upheaval and trauma.”
SNP MP Stuart McDonald said the proposals were “horrendous”.
He tweeted: “The home secretary and prime minister are both determined to rip the Refugee Convention to shreds. Incredibly dangerous proposals.”
Sabir Zazai, chief executive of the Scottish Refugee Council, said the prime minister and the home secretary “must be reminded that integration happens in communities, not in offshore hubs”.
He added: “These plans threaten our commitment to Refugee Convention and will deprive UK of the unique gifts and talents people seeking sanctuary bring to our shores.”
The 1951 Refugees Convention, a United Nations treaty, recognises the right of people to seek asylum from persecution in other countries, allowing them to have rights and benefits in a state.
British journalist Ian Birrell criticised the plan to hold asylum seekers in Rwanda.
“Not only is this a terrible plan but Denmark and the UK are planning to hold refugees in one of the world's most brutal dictatorships, which played a key role in creating so many refugees in its own region,” he said.
But Conservative MP Andrew Bridgen backed the plans, tweeting: “We need to deter illegal migrants from falling into the hands of unscrupulous people traffickers.
“Offshore assessment centres will act as a deterrent and end this miserable trade, while protecting the rights of genuine, qualifying victims seeking asylum.”
Patel has promised a major overhaul of what she called the UK's "broken" immigration system, saying last month she wants a "fully digital border" within five years.
A House of Commons committee was told last November by a human rights lawyer that Australia’s offshore asylum system “does not work”.
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