It is to publish a consultation paper on the family on Wednesday.

Ron Davies: Condemned "lurid and unpleasant lies"

Recommendations include more preparation for those considering marriage, greater help for couples experiencing difficulties and better parenting education in schools.

The launch follows a week in which Welsh Secretary Ron Davies resigned after a "serious lapse of judgement" on Clapham Common in south London.

Paul Boateng: Leave marital breakdowns to the tabloids

Junior Whip David Clelland also announced he was separating from his wife after admitting an affair with his secretary.

Home Office Minister Paul Boateng insisted that fresh newspaper claims about the Davies affair would not alter the government's plans.

Paul Boateng: The family must not be a no-go area for government

He told BBC One's On the Record: "Marital breakdown on Clapham Common - people understand that and they understand it has its proper place.

"Leave that to the tabloids. Serious people and serious programmes recognise that there is an issue out there around pressure on the family."

Mr Davies, MP for Caerphilly, has condemned "the lurid unpleasant lies and fantasies" in some newspaper stories about the incident which refer to Clapham Common being a notorious homosexual haunt.

He said: "It's vicious and hurtful rubbish.

"The only relationship that matters to me is the stable and loving marriage I have with my wife.

The BBC's Daniela Relph: "Mr Davies urges people not to judge him on fabricated fantasies"

"Everybody has a fundamental right to a private life. I am no exception.

"The fact that I have acknowledged a serious lapse of judgement in a particular situation is not an excuse for the media to pay money to any liar who comes along and claims to know me."

Prime Minister Tony Blair is mindful of the scandals that enveloped John Major's government after he embraced a "back to basics" morality drive.

Doomed: The divorce rate has increased six-fold since 1960

And he warned the media not to use this week's announcement as an excuse to "dredge through the private lives of every public figure".

Ministers hope to draw a distinction between what consenting adults engage in behind closed doors - and bringing up children.

But even before its proposals were officially unveiled, Conservatives attacked the government for trying to create a "nanny state".

'Dangerous territory'

Shadow Social Security Secretary Ian Duncan-Smith told On The Record: "It's about 'the state knows best', really it's the nanny state."

Labour MP Lynne Jones warned that "if the government tries to preach, it will be rejected".

Fellow Labour backbencher Malcolm Wicks agreed it was "very, very dangerous territory" for the government to enter.

But he said it was necessary because of the "huge public consequences" that resulted from the fact that 40% of marriages ended in divorce.

The government's proposals come at a time when marriage rates have reached their lowest point since records began. The number of weddings has halved since the 1970s.