David Cameron has been told to raise the issue of LGBT rights at the forthcoming Commonwealth Heads of Government Meeting, which begins on Friday in Sri Lanka.

Campaigners fear any discussion of LGBT rights will remain firmly off the table.

A protest was held yesterday outside the Commonwealth’s Secretariat building in central London against the presence of anti-gay laws in 80% of Commonwealth countries.

On Thursday, the prime minister defended his decision to attend the summit, despite Sri Lanka’s alleged war crimes against the Tamil community and calls for him to boycott the event by Labour leader Ed Miliband.

In Sri Lanka LGBT activists have also been threatened with detention and human rights groups have been told they will be closed down if they continue to campaign for equal rights for LGBT citizens.

Earlier this week, the Kaleidoscope Trust detailed in a report how the situation for campaigners was worsening in the run-up to the summit.

Welcoming the report, Shadow Foreign Secretary Douglas Alexander criticised Sri Lanka’s record on LGBT rights. Calling on David Cameron to raise the issue with his Sri Lankan counterpart, Mahinda Rajapaksa, he said: “New allegations in this report of abuses and intimidation of LGBT citizens are a further warning that President Rajapaksa’s government has not made the progress ahead of this Commonwealth summit that we all wanted to see.”

Downing Street has already said it would be raising the issue of LGBT rights as part of the prime minister’s trip.

The gathering of the Commonwealth Heads of Government Meeting (CHOGM) will be attended by 53 nations, 41 of which have laws banning same-sex sexual relationships.