Former Fianna Fáil minister Pat Carey has expressed concern that his party’s same-sex marriage campaign lacks “energy and urgency”.

Mr Carey, who is gay, attended a meeting on Wednesday night of Dublin-based Fianna Fáil activists who are worried the referendum will not pass. “I’m fairly anxious that the marriage equality referendum would succeed. I didn’t think there was an awful lot happening in our neck of the woods so I thought what could we do about it,” the former government chief whip said.

Mr Carey, who served as minister for community, equality and Gaeltacht affairs from 2010 until 2011, said cultural attitudes towards gay people had changed dramatically in recent years.

Pointing to Minister for Health Leo Varadkar’s disclosure that he was a gay man, Mr Carey said: “My only regret is that I didn’t have the courage or confidence to do what he did.

“When I look back it’s an awful pity I didn’t feel able to do that. Nobody stopped me, but I wasn’t sure how it would be received,” he said.

Mr Carey said he did not know if his former cabinet colleagues knew he was gay. “I said it to Micheál Martin only afterwards, some time in 2011. He didn’t bat an eyelid.”

Mr Carey, who now works in consultancy in the not-for-profit sector, said civil partnership legislation introduced by the government he served in was a “watershed moment”. Prior to that, he said, people spoke differently to and about gay people. “There was a residual crudeness around. Thankfully people are a bit more careful about their use of language and the way they talk about things now, because their best friend could be a gay man or woman.”

He said Fianna Fáil had not yet done enough to assist the passage of the referendum.“This referendum isn’t going to pass because we wish it to. There’s a huge amount of soft support for it but like any campaign it’ll be fought fairly vigorously and people have to be persuaded to come out and vote and, I hope, vote Yes,” he said.