Teenage parents on benefits will be forced to live in "supervised homes" instead of being given council houses, Gordon Brown declared today in a bid to cut the number of pregnancies.

The Prime Minister said it was not right that a 16-year-old girl could "get pregnant, be given the keys to a council flat and be left on her own".

Instead, he told the Labour Party's annual conference in Brighton, groups of young mothers and fathers would be taught responsibility and how to raise their children "properly".

"It's time to address a problem that for too long has gone unspoken: the number of children having children," he declared.

"For it cannot be right for a girl of 16 to get pregnant, be given the keys to a council flat and be left on her own.

"From now on all 16- and 17-year-old parents who get support from the taxpayer will be placed in a network of supervised homes.

"These shared homes will offer not just a roof over their heads, but a new start in life where they learn responsibility and how to raise their children properly.

"That's better for them, better for their babies and better for us all in the long run."

He told delegates: "We won't ever shy away from taking difficult decisions on tough social questions."

The Government is to make available £30 million to local authorities over the coming three years to bring in 500 new places in an existing chain of "foyers", which provide accommodation as well as advice on work, welfare and training to young people.

Between 10 and 100 young people live in each foyer, run by principals supported by a team of workers who apply strict sets of rules. Youngsters who break behaviour contracts can be thrown out or moved on to other homes.

By the end of 2012, all eligible 16 and 17-year-olds - including young parents - who apply for social housing will instead be offered a place in one of these units.

Government sources stressed that there would be no compulsion for 16 and 17-year-old mums to move to a supervised home if they are able to stay at home with their parents.

Once sufficient supported accommodation has been provided, legislation will be introduced that no-one aged 16 or 17 can be left alone in social housing without support or rules.

Single parent charity Gingerbread urged the Government not to make "misleading" claims about young people.

Chief executive Fiona Weir said: "Damaging myths abound about young parents and it's vital that politicians don't reinforce these.

"Just 3% of all births in 2007, the latest available data, were to mothers under 18 and teenagers make up just 2% of single parents.

"Far from 'being handed the keys to a council flat' young people under 18 are in fact not allowed to hold a tenancy.

"Most teenage parents already live at home and homeless 16 and 17-year-olds are already supposed to be offered supported accommodation by their local authority.

"More investment in making this supported accommodation a reality across the country would be welcome - but it must not be accompanied by rhetoric that risks reinforcing myths about teenage parents."

Lords Leader Baroness Royall defended the proposals which formed part of a "socially responsible" speech by Mr Brown.

She said: "He is not talking about ghettoising single mothers, he is talking about helping them on their way to be better parents and members of society."

Clare Tickell, chief executive for Action for Children, warned against a "one-size fits all approach".

She said: "It is vital that we look at the best way of helping teenage parents to develop their parenting skills, improve their employment prospects and break free of issues that have been passed down though generations.

"Through our own work with teenage parents, we know that they want to provide their child with the best possible start in life-and that they grasp the opportunity to receive practical and emotional support on how they can best do this.

"However, any help must be offered through a package of support, tailored to their needs and available in their local community.

"A one size fits all approach will only risk making young parents feel even more isolated and stigmatised."

Hilary Pannack, chief executive of Straight Talking Peer Education, a charity which tries to get young parents back into education and work, said: "This is not the 'unspoken' problem Gordon Brown speaks of.

"The Labour Party has had a strategy in place for 10 years which has done little to reduce teenage pregnancy or get teenage parents back into education, training or work.

"There an assumption in Gordon Brown's speech that all teenage parents are bad parents but this is simply not the case.

"The Prime Minister says it can't be right to hand over council flat keys to a 17-year-old, but that doesn't happen anyway. Young parents need more support than just housing.

"His offer of places for teenage parents in supervised mother-and-baby units is not new. It's been this Government's policy since at least 2003 to require local councils to provide supported housing for all lone parents under the age of 18.

"And who is going to manage these new supervised units and what support or training is in place to do it?"

Ms Pannack added: "We need a system of 'floating support' services, as used already in Somerset, so that teenage parents can be near their families, assuming they're supportive, rather than an unrealistic pledge to create a network of supervised units across the UK."