The UK’s most senior family judge was under fire from politicians, colleagues and family rights campaigners yesterday after saying that the collapse of the traditional family was to be welcomed.

In a speech Sir James Munby, president of the Family Division of the High Court, celebrated the “infinite variety” of contemporary forms of family life, including single parents, temporary cohabitation, same sex and polyamorous arrangements, and children born of artificial donor insemination and surrogacy arrangements. “The fact is that many adults and children, whether through choice or circumstance, live in families more or less removed from what, until comparatively recently, would have been recognised as the typical nuclear family. This, I stress, is not merely the reality; it is, I believe, a reality which we should welcome and applaud.”

The Marriage Foundation, founded by Sir Paul Coleridge, the former High Court family judge and colleague of Sir James, was fiercely critical of the Judge’s remarks. Its research chief, Harry Benson, said: ‘Sir James has stepped well outside the court in saying “we should welcome and applaud the end of the nuclear family”.

‘At a time when we have the highest rates of family instability in the entire developed world precisely because of the trend away from relatively stable marriage, this is like saying that we should welcome and applaud the existence of ill health or broken legs. Yes, we must care for, support, treat and prevent brokenness. But to welcome and applaud it is a rare lapse of judgment.’

Sir James’s remarks were also criticised by Iain Duncan Smith, the former Tory leader and work and pensions secretary, who has long argued for greater state support for married couples. ‘The UK faces a complete collapse of family commitment through marriage, particularly among people who are on low incomes.’ Mr Duncan Smith said that the cost of family break-up to the state is estimated to run to £50 billion a year. ‘If that was caused by something economic the Government would move heaven and earth to stop it,’ he said. ‘But because we are afraid of offending people we have failed to do anything. We should be moving to stop family break-up.’