Australian Prime Minister Scott Morrison reacts during Question Time in the House of Representatives at Parliament House in Canberra, Australia, November 27, 2018. AAP/Mick Tsikas/via REUTERS

MELBOURNE (Reuters) - Australia’s Liberal party passed new rules late on Monday to make it harder to depose its leader, as the ruling coalition grapples with sinking opinion polls ahead of an election next year.

The new rules require a two-thirds majority to change an elected leader, promising greater leadership stability after Australia’s revolving door of five prime ministers in little more than five years.

“It has been to the great anguish of the Australian people, as they have seen this happen in the Labor and the Liberal party,” Prime Minister Scott Morrison told the media in Canberra, the capital.

“And they’re sick of it...and it has to stop.”

The new rules will apply to leaders who successfully contest an election, Morrison added, thus opening the door to a challenge for the party’s top job if the ruling Liberal-National coalition loses next year.

The coalition is staring down the barrel of a heavy election defeat in the next six months following backlash from voters over yet another leadership spill, in August, when then prime minister Malcolm Turnbull stepped down.

Monday’s move followed Morrison’s return from a meeting of the G20 grouping in Argentina, where Germany’s Chancellor Merkel was photographed reading briefing notes on Morrison, who also talked President Trump through the process of a political spill.

In 2013, Australia’s Labor party reformed its leadership rules under Prime Minister Kevin Rudd, adopting rules that required 75 percent of the party room to agree before a change in the elected leader.

Since then, opposition leader Bill Shorten has been unchallenged as leader of the Labor party.