A Free Presbyterian minister has warned against legalising equal marriage in Northern Ireland, describing it as a “huge propaganda campaign”.

Rev Ian Brown, who succeeded Dr Ian Paisley at the Martyrs’ Memorial in Belfast, told BBC Radio Ulster: “I know there is significant opposition to it at this moment in time, and I would trust that will be maintained, but I am always aware that we are campaigning against a huge propaganda campaign.”

He added: “Any time I would tune in to BBC Radio Ulster, including Sunday Sequence and the Nolan Show, it is given a prominence that it doesn’t deserve if you are talking about one per cent and not many more of the population. You are talking about a miniscule proportion of the population that this whole campaign is being driven on behalf of.”

In response, Andrew Muir, the openly gay mayor of North Down, said a fresh debate on the issue could bring similar legislation to the Province.

“In order for that to become a reality in Northern Ireland, we need to engage in a widespread discussion across society to get agreement on that,” he said.

“Northern Ireland has changed quite a lot as a society. A majority of the electorate would be in favour of equal marriage, and that is to be welcomed – but for that to become a reality requires legislation from Stormont and to date that hasn’t happened.”

Northern Ireland is the only remaining UK nation where equal marriage has not been legalised.

The Equal Marriage Northern Ireland Campaign held two demonstrations at Belfast City Hall and the Guidlhall Square in Foyle last Friday.

The Democratic Unionist Party (DUP) has twice used a petition of concern to block votes on equal marriage – much to the annoyance of Sinn Fein, the Greens and the Alliance Party, who all support the reform for Northern Ireland.

Under Stormont rules, any party can trigger a petition of concern on a motion that then can only pass if the majority of nationalists and unionists back it together.

A joint same-sex marriage proposal by Sinn Fein and the Green Party was defeated in October 2012, along nationalist and unionist lines.

The DUP again blocked progress on equal marriage through another petition of concern in April 2013.