FEDERAL Labor MPs from the Right faction say they will cross the floor and risk expulsion rather than vote for gay marriage, should the party change policy to one of support rather than a conscience vote.

The Prime Minister, Julia Gillard, supports changing policy from opposition to a conscience vote at the ALP national conference, starting tomorrow, but the Left will push for a policy of outright support.

Julia Gillard … opposes gay marriage. Credit:Joe Armao

The Right which usually controls the numbers, is divided and a number of defectors are planning to support the Left. Sources said numbers are very tight and unless somebody backs down, there is a threat Ms Gillard could be rolled.

A handful of Right MPs, including Chris Hayes from western Sydney, told the Herald yesterday they would never vote for gay marriage, even if party policy dictated it.