FINE Gael TDs last night said they had no problem speaking to church figures who want to lobby them over abortion.
The news came after Communications Minister Pat Rabbitte yesterday told the Catholic Church to stay out of the political debate on the issue.
Dr Brady said the church thinks "a referendum is the only solution" and would vigorously resist any moves to bring in abortion.
"We would have a media campaign, we would be lobbying public representatives and also hope to write a pastoral letter on this situation setting forth the argument we have always held," he said.
Mr Rabbitte said he was "surprised" when he heard "the cardinal's reference to lobbying and engaging, canvassing public representatives".
"I don't welcome the cardinal promising to engage in the political campaign," Mr Rabbitte told RTE radio.
"I have no objection to the cardinal setting down his traditional view. But I think we have reached the stage in this country where we acknowledge the role of different faiths in our society and there ought to be separation between church and state.
He also said the Government saw no necessity to have a referendum.
"I talk to all sides on big issues, including the church and I will be doing so again on this one," Mr O'Mahony said.
"I don't think anyone should be precluded from talking to us. There was a time when the perception was the cardinal of the day would dictate policy, but that's not the case any more."
Carlow Kilkenny's John-Paul Phelan said everyone should be allowed get in touch with their TDs. However, his Fine Gael constituency colleague Pat Deering said he believed the church hierarchy should stay out of the debate.
Ministers fear the expert report on abortion, which is due to be presented to Health Minister James Reilly next month, could spark yet another divisive culture war.
The group drafting the report is tipped to recommend legislating for abortion, rather than holding a referendum.
"I hope that report doesn't come for 10 years, but it's coming and we're going to have to deal with it," one minister said.
Kieran Rose of the Gay and Lesbian Equality Network (GLEN) said Catholic bishops are entitled to their opinions but said "equal access to civil marriage for lesbian and gay couples is a matter for the State".