Labor MPs and Senators will not be bound to vote for same-sex marriage until 2019.

After hours of negotiations the party’s Right faction cobbled together the numbers to amend a motion from the Left that would have forced MPs and Senators to be bound in the next term of Parliament.

Labor leader Bill Shorten moved the revised motion and pledged to introduce legislation to legalise same-sex marriage if he wins government.

• Labor MPs to resist ‘force’ on gay marriage

“What the Labor Party does with this resolution is we lay down the challenge to Mr Abbott and his Liberals – please give your Members of Parliament a free vote so we can make marriage equality a reality now,” he said.

“Marriage equality is a simple overdue change.”

As part of the deal Mr Shorten promised to introduce the legislation to legalise gay marriage within 100 days of winning government.

Deputy leader Tanya Plibersek had been pushing for a binding vote but seconded Mr Shorten’s motion.

“I still hope we can have marriage equality by Christmas, but if this Parliament doesn’t pass marriage equality a Shorten-Labor government will within its first 100 days,” she said.

“You know he’ll deliver in government.”

Both Mr Shorten and Ms Plibersek urged the Coalition to allow its members to have a conscience vote too.

Just hours earlier, left wing delegates were confident their motion to bind members on a vote would be passed at Sunday’s national conference.

-ABC