Nearly half of British children now grow up outside the traditional two-parent household, according to a report on the make-up of the modern family.

A review being published today by Dame Rachel de Souza, the children’s commissioner for England, has found that almost a quarter of families are headed by a lone parent, compared with the EU average of one eighth.

Forty-four per cent of those born in 2000 will have spent some of their childhood up to age 17 outside a traditional “nuclear” family, compared with 21 per cent of people born in 1970.

Before the appointment next week of the new prime minister, de Souza has urged the government to centre policy on families. She will revise the “family test”, which is applied to all new domestic laws and policies, to put families “at the heart” of policymaking.