Tories: 'We'll stand up for marriage'

The Tory leader said that there was something 'deeply wrong' with the nation despite its continued economic prosperity.

He highlighted high rates of teenage pregnancy, drug abuse, failing schools, crime rates and prison populations in Britain compared with other European countries.

A landmark Tory report to be published tomorrow is designed to draw clear battle lines with Labour, paving the way for tax breaks and benefit reforms in favour of married couples and families. It will also recommend:

• Raising tax on alcohol by up to 10 per cent to combat binge drinking • Reclassifying cannabis as a Class B drug;

• Forcing heroin users to go 'cold turkey' rather than be given substitutes such as methadone.

Mr Cameron said the major cause of society's ills was family breakdown. And he claimed Labour policies encouraged couples to split up by discriminating against two-parent families.

"We need to go right through our tax and benefit system and ask ourselves why is it encouraging people to live separately," he said.

"Many couples choose not to get married, and that is absolutely their decision. The point I'm making is that marriage is a good institution. It should be supported. It should be recognised in the tax system."

Mr Cameron's analysis was backed by former Labour welfare minister Frank Field, who argued that Gordon Brown's tax system 'wallops' two-parent families.

He said a single parent with two children working 16 hours a week gained a weekly income of £487 thanks to tax credit payments.

But the breadwinner in a two-parent family, also with two children, is required to work 116 hours to get the same income.

The Prime Minister has firmly rejected the idea of tax breaks in favour of married couples, arguing they would unfairly penalise children with unmarried parents.

A Labour source said last night: "Lewis Hamilton was racing today at Silverstone, having been raised single-handed by his father doing three or four jobs to give him the best opportunities in life.

"For the Tories to be saying they would rather support a father on his fourth marriage and eighth child, just because of a wedding certificate, than people like Lewis Hamilton's dad is going to take some explaining."

But Mr Cameron said he made no apology for speaking up for marriage. Half of all unmarried couples separate by their child's fifth birthday, compared with just one in 12 married couples, he told the BBC's Sunday AM programme.

"The evidence is incredibly strong," the Tory leader said. "We need a big cultural change in favour of fatherhood, in favour of parenting, in favour of marriage."

"I think this is absolutely the big question, the big argument of our times. Kids do best if mum and dad are there to look after them.

"And today we have a benefit system that encourages families to break up, encourages couples to be separate. These things have got to change."

The report - Breakthrough Britain - will set out radical policy proposals to address the causes of social and family breakdown.

Drawn up by a policy group headed by former Tory leader Iain Duncan Smith, it will not be binding on the party, although Mr Cameron has let it be known he is hugely impressed by the arguments. He is expected to set out firm policy pledges at this autumn's party conference.