Two men who were subjected to a suspected homophobic robbery in London, are urging politicians to change language used during the debate around equal marriage, for fear that homophobic attitudes are being legitimised by negative comments.

The gay couple who were walking through a park in south London during the early hours of Sunday were viciously assaulted by a gang of men with one of the attackers saying “stay down faggot.”

The incident happened on Sunday 19 May at around 12:30am.

Christopher Bryant, 42, the editor of gay and lesbian online magazine Polari, and his partner Damon Truluck, 38, were walking home across Betts Park in Penge, in the London Borough of Bromley, when six men approached them.

With Parliament gearing up for today’s third reading of the Marriage (same sex couples) Bill today, Mr Bryant said he was worried that homophobic attitudes are being legitimised by politicians’ testimony around the issue, reports the Independent.

“It is about giving people a legitimate narrative. At the moment MPs are saying ‘the situation is not equal for you’. By denying active equality they are inherently saying there is something wrong with [being gay], without actually saying it,” he said.

“A lot of kids in particular seem to be as homophobic now as they ever were. Our social circles tend to be limited. We tend to circulate with like-minded people, it is only when we step out of those worlds that we realise there is so much we don’t see.”

Before the attack, both men were raising awareness of Friday’s International Day Against Homophobia and Transphobia.

Gay rights charity Stonewall has described the attack as “shocking”.

The Metropolitan Police Service has launched an investigation and the couple gave a further statement to police on Monday.