BBC Social Affairs editor Niall Dickson: "Many teenage mothers would never even consider adoption"

But social workers and groups working with single mothers reacted angrily to Jack Straw's suggestion that adoption should be seen as a "positive, responsible choice".

In a speech to a Family Policy Studies Centre conference, Mr Straw pointed out the fall in the number of adoptions and said it should be promoted to young pregnant women.

The President of the Association of Directors of Social Services, Chris Davies, said he was unclear if Mr Straw had meant social workers should take this initiative.

Chris Davies, President of the Assn of Directors of Social Services gives his response

"If he did mean social workers, the world's just not like that," he said.

"Young women who are pregnant and undecided, they come to their decisions with their family, their friends, their partner, perhaps the doctor, they very rarely talk to a social worker at all - so our influence on the number of babies being offered for adoption is negligible."

One group working with young women carrying unwanted pregnancies was horrified by the home secretary's proposals.

"Adoption is an entirely inappropriate solution to the problem of teenage parenthood," said Ann Furedi of the British Pregnancy Advisory Service, which provides abortion advice and help.

"Fewer than 100 newborn babies a year are handed over for adoption, not because of legal difficulties, but because of the emotional difficulties a woman faces when she gives away the child that she has borne."

Jack Straw: "I'm quite unrepentant about what I said"

But Mr Straw defended his comments, saying evidence showed children put up for adoption did better than those taken into care.

He insisted he was not urging all single mothers to give up their children.

Jack Straw: Remove barriers to adoption

"Everybody knows that some teenage mothers may not have the necessary skills to look after their children during their childhood," he told BBC Radio 4's World at One.

He said he wanted to start a rational debate on what was in the best interest of children born into such circumstances, but expected criticism.

"You always pay a penalty for saying things for the first time," he added.

The minister's comments follow the case of the Bramley family who went on the run after being told they could not adopt two girls in their care.

In his speech, Mr Straw said: "It is still a sad fact that many suitable couples have been on waiting lists far too long, while children have remained in care."

In particular, he expressed concern at the number of young babies in care. In 1997 there were more than 3,500 children aged under two-years-old being looked after by local authorities.

Mr Straw said that although it was a sensitive area, it was in no-one's interests for a baby to suffer in its first year because the mother - often a teenager - proved unable to cope.

Mr Straw said new guidelines had already been issued to local authorities to relax adoption policies, but more work needed to be done to match up would-be parents with children.

He welcomed the "overwhelming" public response to the government's consultation paper on supporting families published last year.