A furious backlash has erupted after it emerged that only 350 lone child refugees will be brought to Britain from Europe under the so-called Dubs Amendment.

The number is well below the 3,000 campaigners originally called for the UK to accept.

Opposition politicians unleashed a wave of criticism, denouncing the development as shameful and a betrayal and accused Theresa May of "abject moral failure".

Ministers introduced the scheme last year after coming under intense pressure to give sanctuary to lone youngsters stranded on the Continent.

Calls for the measure were spearheaded by Labour peer Lord Alf Dubs, whose amendment requires the Government to relocate unaccompanied refugee children from other countries in Europe.

The clause did not specify a figure but on Wednesday it was revealed that 200 have so far arrived through the route - and it will close once another 150 have been brought to the UK.

Lord Dubs said: "Britain has a proud history of welcoming refugees.

"At a time when Donald Trump is banning refugees from America, it would be shameful if the UK followed suit by closing down this route to sanctuary for unaccompanied children just months after it was opened.

"During the Kindertransport Sir Nicky Winton rescued 669 children from Nazi persecution virtually single-handedly. I was one of those lucky ones.

"It would be a terrible betrayal of his legacy if as a country we were unable to do more than this to help a new generation of child refugees."

Liberal Democrat leader Tim Farron attacked the Government for a "betrayal of these vulnerable children and a betrayal of British values" while Green Party co-leader Jonathan Bartley described the announcement as "an absolute disgrace".

Labour MP Yvette Cooper, chair of the Commons Home Affairs Committee, said: "The Government is completely wrong to close down the Dubs scheme and they are going against the spirit of Parliament's amendment last year.

"The Government needs to change track urgently and revive the Dubs scheme so Britain can carry on doing our bit to help."

The 350 figure was disclosed in a written statement from Immigration Minister Robert Goodwill.

It is the first time the Government has given a number for how many under-18s will be resettled under the Dubs process - officially Section 67 of the Immigration Act.

The total was reached after consultation with councils on their capacity to care for and support asylum-seeking children.

Mr Goodwill said: "Local authorities told us they have capacity for around 400 unaccompanied asylum-seeking children until the end of this financial year.

"We estimate that at least 50 of the family reunion cases transferred from France as part of the Calais clearance will require a local authority placement in cases where the family reunion does not work out."

In total 900 unaccompanied asylum-seeking children were transferred to the UK from Europe last year, including more than 750 from France as part of Britain's support for the clearance of the Jungle camp in Calais.

More than 200 of those children met the criteria for the Dubs route, while the remainder were transferred under an accelerated process based on the Dublin Regulation covering family reunion cases.

Mr Goodwill added that the Government will continue to meet its obligations under Dublin, and accept responsibility for processing asylum claims where the UK is determined to be the responsible member state.

No date for the closure of the Dubs scheme has been given but it is expected that the remaining arrivals will be completed this year.

David Simmonds, chairman of the Local Government Association's Asylum, Refugee and Migration Task Group, said: "Councils demonstrated tremendous leadership at a local, regional and national level in resettling the children from the Calais camp.

"The number of unaccompanied asylum-seeking children living in England increased by more than 50% to over 4,000 in the last year, and the vast majority of councils are already providing care and support for these vulnerable children and young people."

Labour's Shadow Home Secretary Diane Abbott said: "My colleague Lord Alf Dubs is right, this is shutting the door on the most vulnerable.

"The Government must end these efforts to prevent refugees arriving here. This is not who we are.

"The minister is wriggling out of the Government's obligation to accept child refugees.

"But the internationally agreed principles and the Dubs Amendment were never conceived as a 'one-off'.

"They should continue to commit to meeting their international treaty obligations and our own laws."

Stuart McDonald, the SNP spokesperson on Immigration, Asylum and Border Control, said: "Theresa May is guilty of abject moral failure; showing callous disregard for some of the world's most vulnerable children.

"It is shameful and completely unacceptable for the UK Government to turn its back on child refugees in the midst of the worst humanitarian crisis since the Second World War."

The Cumbernauld MP said that after many months of inaction, the UK Government had only reluctantly agreed to resettle a fraction of the estimated 90,000 unaccompanied child refugees in Europe following huge pressure from the public, parliament and the Scottish Government.

"To now go back on its word and close down this key route prematurely further compounds the shameful behaviour of Theresa May and her Tory ministers throughout the Syrian refugee crisis.

"Given the scale of the humanitarian crisis, and the comparative efforts of other countries, the UK Government should significantly step up - not close down - its refugee resettlement efforts."

Mr McDonald pointed out that Canada, a country with half the population of the UK, had taken more than 35,000 Syrian Refugees in 2016 alone, while Germany received around 300,000. In comparison the UK Government’s efforts had been "pathetic and bring shame to a country with a proud tradition of accepting refugees".

He added: "As we have said time and again Scotland stands ready to do its bit. We have already welcomed well above our population share of those Syrian refugees resettled in the UK and we are willing to do more but the UG government cannot shirk its responsibilities and the Prime Minister must now show some leadership and u-turn on this disgraceful decision."