Children as young as four may be given compulsory sex education lessons, MPs have said.

A cross-party group of MPs is calling on the Government to make advice on sexual health and relationships mandatory in all schools.

The MPs, led by Chris Bryant, a Parliamentary aide to the Labour deputy leader Harriet Harman, said the answer is to give children more information about sex, contraception and relationships.

The appeal comes as ministers draw up plans to extend the scope of sex education provided in schools.

Britain currently has one of the highest teenage pregnancy rates in Europe and figures suggest that rising numbers of young people are being diagnosed with sexually transmitted diseases.

Under current rules, schoolchildren must be taught the biological facts of reproduction, which usually happens in science classes.

Every school must have a sex education policy, but there is no statutory requirement for teaching about relationships and the social and emotional side of sexual behaviour.

Critics argue that sex education in primary schools risks sexualising children at a younger age.

Campaign group the Family Education Trust said there is no evidence that teenage pregnancy rates are reduced by starting sex education at an early age.

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