07/08/2017 11:24 AM AEST | Updated 07/08/2017 12:14 PM AEST

There's A Rainbow Hanging Over Parliament Before Liberals Meet On Same-Sex Marriage

How is this for timing?

Andrew Meares/Fairfax
I's time. A rainbow forms over Parliament House in Canberra.

CANBERRA -- Here's a message from above that is hard to miss on the day the Liberal Party holds a special party room meeting on same-sex marriage.

A well-timed and positioned rainbow, the symbol of LGBTQ pride, formed over Parliament House in Canberra on Monday morning.

The brief appearance of the meteorological phenomenon, captured by Fairfax photographer Andrew Meares, came as Liberal parliamentarians arrived ahead of the 4pm party room meeting called by Prime Minister Malcolm Turnbull to thrash out the party's same-sex marriage position for this term of parliament.

Liberal senator Dean Smith and five lower house MPs -- Warren Entsch, Trevor Evans, Trent Zimmerman, Tim Wilson and Jason Woods -- have argued for MPs to be given a conscience vote in Parliament on a private member's bill prepared by Smith that would allow same-sex couples to marry.

Another Liberal voice joined them on Monday with John Alexander also calling for a conscience vote in Parliament.

But support has been growing within the Liberal Party for a postal plebiscite to get around the need for legislation to fund it. Legislation to fund the original plebiscite failed in a hostile senate and it is expected to maintain that stance.

A promise is a promise to former Prime Minister Tony Abbott. At least on this issue. He has argued, in the Australian newspaper on Monday, that Coalition MPs are "honour-bound to oppose same-sex marriage in the absence of a plebiscite that's supported it".

Abbott said, at least for this term of parliament, Coalition MPs must remain committed to the position that they "collectively and individually took to the election last year".

Andrew Meares/Fairfax
A rainbow flies over Parliament House in Canberra.

Marriage equality campaigners expect to mount an immediate High Court legal challenge to a postal plebiscite based on legal advice that it also requires an appropriations bill to fund it and without one passing parliament it would be unconstitutional.

Frustration, in and out of the Liberal Party, is growing.

"Quite frankly, I am over it," Warren Entsch told HuffPost Australia. "I think the majority of Australians are over it. They just want the bloody thing to go away."

"This is an issue that's never going to go away until it's resolved. Until there is a vote in the parliament."