The British government could force Gibraltar to equalise the age of consent for gay men if the territory does not take action to change the law.

Gibraltar currently allows lesbians and heterosexuals to have sex at 16, but the age of consent for gay men is 18. Anal sex is illegal between men and women.

This contravenes international human rights laws and the Gibraltar government has asked the Supreme Court to rule on whether the difference breaches the constitutional rights of gay men.

According to the Gibraltar Chronicle, Britain could amend the territory’s laws for it if the territory does not take the step itself.

A spokesman for the Foreign and Commonwealth Office said: “The UK has a modern and mature relationship with its overseas territories which involves allowing them to manage their own affairs to the greatest degree possible.

“We have always stated that we would prefer overseas territories governments to amend the legislation themselves, rather than us amend by Order in Council.”

In 2008, foreign secretary David Miliband told the Commons’ Foreign Affairs Committee that Britain would strongly encourage territories to comply with international law or remedy laws itself through local legislation.

He said: “However, where it is clear that a territory government is not prepared to take the necessary action, we are ready, where possible, to take steps to remedy the defect.”

The Gibraltar government’s arguments against lowering the age of consent for gay men were published last week.

It argues that the matter can be justified on health and religious grounds.

Documents said: “Religious faith plays an important role in our community and is also an important part of its social cohesion which would be undermined.”

On health, they added: “widening the range of sexual practices which can be committed with young people puts even more pressure on them to be sexually active and there is no doubt that anal sex carries greater health risks than heterosexual intercourse.”

The government also argues that it is heterosexuals being discriminated against, rather than gay men, as straight couples are completely banned from having anal sex.