Every new domestic law or Government policy will have to pass five tests to ensure it is family-friendly before being approved by ministers, under guidance released by Work and Pensions Secretary Iain Duncan Smith.

Officials developing proposals will have to consider their impact on family formation; on families going through key life-changes; on separated couples and on families at risk of breakdown, as well as on the ability of all family members to play a full part in family life.

Prime Minister David Cameron first announced plans for a "family test" in a speech this summer, when he said it would ensure that "every single domestic policy that Government comes up with will be examined for its impact on the family".

Citing benefit rules which create incentives for couples to live apart and bureaucratic red tape which blocks loving couples from adopting as examples of policies which had been crafted without consideration of their impact on families, Mr Cameron told the Relationships Alliance in August that Government initiatives should "help families come together (and) stay together".

Unveiling the new guidance, which was drawn up in consultation with family experts including the Relationships Alliance, Mr Duncan Smith said that it would require all Whitehall departments to understand fully how their policies support strong family relationships as well as identifying and addressing any that could undermine them.

Civil servants developing policy and legislation will be required to consider five questions:

:: What kinds of impact might the policy have on family formation?

:: What kind of impact will the policy have on families going through key transitions such as becoming parents, getting married, fostering or adopting, bereavement, redundancy, new caring responsibilities or the onset of a long-term health condition?

:: What impacts will the policy have on all family members' ability to play a full role in family life, including with respect to parenting and other caring responsibilities?

:: How does the policy impact families before, during and after couple separation?

:: How does the policy impact those families most at risk of deterioration of relationship quality and breakdown?

"Families are the foundations of society - and we know that strong and stable families can have a huge impact on improving the life chances of our children," said Mr Duncan Smith. "So in order to build a stronger society we must ensure we support them, and the relationships on which they are built.

"This is the truest representation of Government on the side of hard-working families in Britain - demonstrating a clear and unqualified commitment to strengthening and supporting family life for our children and for generations to come."

Ruth Sutherland, chair of the Relationships Alliance and chief executive of marriage and relationship guidance charity Relate, said: " This is an important step towards putting families and relationships at the heart of public policy, something we have been campaigning passionately for.

"We are proud to have supported the development of the test and we look forward to seeing it in action, helping policy-makers to put the interests of all families at the centre of their work."

Fiona Weir, chief executive of single parent charity Gingerbread, said: "The family test has the potential to make Government policies work better for families of all shapes and sizes. One in four families in the UK is headed by a single parent, so it's absolutely essential that the test takes their needs into account, alongside those of other families."

Samantha Callan, associate director for families at the Centre for Social Justice think-tank, said: "Family breakdown can devastate communities and cause lifetime disadvantage. But it is not inevitable.

"Strong, stable families are the bedrock of society. Successive governments have avoided taking action to build stability in Britain's homes because they have been nervous of talking about families. Hopefully today's announcement marks the beginning of a fresh start for family policy.

"We can't afford for family stability to continue as a political afterthought. I hope the new test will put it at the heart of public policy - where it belongs."