Labour grandee and former Home Secretary Jack Straw has backed a controversial proposal to use dental checks to determine the age of child refugees from the Calais "Jungle" camp hoping to join their families in the UK.

"Officials made a judgment, we have to accept that judgment, but if there is a case for dental checks, I would certainly not as home secretary have ruled that out," he told the Daily Mail on Thursday morning (20 October).

The comments come after Conservative MP David Davies, the chair of the Welsh Affairs Select Committee, was widely criticised for making the proposal.

Former England footballer and BBC presenter Gary Lineker even weighed into the debate, branding the treatment of child refugees as "hideously racist and utterly heartless".

But Straw warned public confidence in the UK's asylum system could be undermined if the rules are flouted.

"What I would say to those supporting an increase in numbers of refugees to come here is this: if it turns out those coming in here are over 18 – and the truth will emerge after a while – then it will undermine public confidence in the whole system," he said.

"So having tests, providing they are not too intrusive and invasive, is actually a sensible thing to do for everyone concerned. Most of them are economic migrants and you have to be pretty firm about this."

The British Dental Association (BDA) have condemned the proposed age tests as "inappropriate and unethical", while welcoming the Home Office's decision to rule out such a move.

"We're pleased the Home Office has finally ruled out the use of dental x-rays on child asylum seekers," said Judith Husband, chair of the BDA's education, ethics and the dental team working group.

"It draws a line under 10 years in which ministers have kept flirting with an eye-catching, but ultimately ineffective, policy. Dental X-rays were never going to be a silver bullet for verifying age. They aren't cheap, they aren't simple, and at the end of day they don't provide definitive results."

Labour's former immigration Liam Byrne failed to rule out backing dental age checks of asylum seekers in 2007, a BBC report said.