President Gary Spence's email, sent to LNP members, is being read as a sign that Mr Evans' could face a threat to his preselection as the Member for the seat of Brisbane.

In the email Mr Spence stressed the LNP's position is to support a plebiscite or a postal ballot and said it was "unfortunate" that some elected LNP MPs have been "contributors" to the media coverage on same sex marriage by canvassing favouring a private members bill and free vote in parliament.

On Monday Mr Evans told News Corp that with the parliament rejecting the plebiscite, a breakthrough in the stalemate was needed and he did not rule out crossing the floor to help bring on a vote on gay marriage. He also appeared on the ABC's Lateline that evening.

Mr Spence did not once name Mr Evans in the email but his target was clear.

"I am disappointed that views that do not accord with the Party's policy have been aired publicly. I am equally disappointed that members elected under the LNP banner have chosen to take a position that defies LNP policy and the wishes of the LNP's membership," he said.

Mr Spence went on to describe same sex marriage as a "distraction."

"The community has a valid expectation that their elected parliamentarians should work to solve the issues that really matter to them – job security, reducing household costs, capping electricity prices and much more.

"I encourage all our members to focus on what concerns the majority of Australians, and not be distracted by matters peripheral to the everyday fundamentals that Australian families need for a prosperous future."

Mr Spence said if any MPs had concerns about party policy they should have raised it at the party's convention in July. Mr Evans did not raise the issue at the meeting, but same-sex marriage was not listed on the agenda and members moved an urgency motion without notice on the Friday afternoon.

Mr Evans is gay and worked twice as a staffer for the conservative cabinet minister Peter Dutton, who is widely viewed as a potential successor to the Liberal leadership.

Mr Dutton has been spruiking the postal ballot option but it's understood he and the other leading conservative in Cabinet, Mathias Cormann, also believe the issue needs to be resolved. 

On Tuesday Prime Minister Malcolm Turnbull refused to comment on whether MPs who crossed the floor on the issue could have their preselections threatened. Four MPs are understood to be willing to cross the floor including Queenslanders Warren Entsch and Trevor Evans, Victorian Tim Wilson and New South Wales moderate Trent Zimmerman. 

Liberal Senator Dean Smith has drafted a private members bill which could be put to parliament in August or September.