Northern New South Wales Nationals MP Kevin Hogan has become the third National to back gay marriage this week, but only on the condition that churches are not forced to marry same-sex couples.

“I want churches to be very much protected, and to be legislatively protected, that they do not have to marry gay couples if it is against the values of their church,” he said.

Mr Hogan also said he was in favour of a referendum style ballot as he would “prefer the people to make the decision”.

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On Wednesday, senior cabinet minister Nigel Scullion declared his support for same-sex marriage.

The Indigenous Affairs Minister told Radio National’s Drive program he “absolutely” believed in the “concept” of gay marriage and thought there should be a conscience vote on the issue.

“But you shouldn’t confuse my view with how I vote on a piece of legislation I haven’t thus seen,” Mr Scullion said.

A cross-party bill to legalise same-sex marriage is expected to be introduced into Parliament later this year, and neither the National nor Liberal parties have decided whether MPs and senators will be given a free vote on the issue.

On Tuesday, Victorian Nationals MP Darren Chester revealed he was in favour of gay marriage.

“I support a conscience vote. I think that conscience vote should occur in the spring sitting of the Parliament,” he told ABC’s 7.30 program.

“And it would be my intention, if there was a conscience vote awarded, to vote yes.”

Mr Chester said he felt the mood of the community in his Gippsland electorate had changed, with more voters supporting same-sex marriage than in the past.

Gay marriage discussion ‘a distraction’, Nationals chief whip says

The Nationals chief whip Mark Coulton, who is against same-sex marriage, said the debate was a distraction from other government business but should not be rushed.

“It is distracting but if there was a process outlined then maybe the urgency and the intensity, and I guess the emotion, that’s in the argument at the moment might back off a bit,” he said.

“I think that largely the Prime Minister is working his way through that now.”

Mr Coulton said Liberal MP Philip Ruddock’s suggested model described on Q&A on Monday night, for consideration to be given for the state to register relationships and churches to deal with marriage, has merit.

“The state only deals with the issue of the registration of relationships and the churches, and other institutions, deal with what has been marriage as we understand it,” he said.

Nationals senator Matt Canavan said the party had to discuss its position.

“I think when we do, we will strongly defend traditional marriage,” he said.