SYDNEY (AFP, Reuters) - Australia shelved plans to embed carbon emissions targets in law on Monday (Aug 20), after a party revolt against embattled Prime Minister Malcolm Turnbull.

With its heavy use of coal-fired power and relatively small population of 25 million, Australia is considered one of the world's worst per capita greenhouse gas polluters.

With Australia's east coast in the middle of the worst drought in 60 years, Turnbull said his government would seek to legislate emission reductions in the future.

He gave no timetable for revisiting the issue, but said his government is committed to its Paris accord commitments.

"The legislation to move forward with the emissions component of the National Energy Guarantee will not be able to pass the House of Representatives," Turnbull told reporters in Canberra.

Monday's decision drew immediate scorn from critics, who argued it was meaningless to be committed to a treaty without working to hit its targets.

"It's a complete capitulation to the right wing members of the Liberal Party of Australia, who want to perpetuate Australia's coal economy," said Robyn Eckersley, Professor and Head of Political Science at University of Melbourne.

The change also drew criticism from Australia's energy sector.

"One of the things that's been missing in the whole energy sector is certainty around carbon policy. That's what has stalled investment. And this just continues that," Carl Kitchen, a spokesman for the Australian Energy Council, said of the decision to remove emissions targets.

Turnbull's predecessor Tony Abbott was in charge when Canberra agreed to cut emissions by 26 per cent by 2030 as part of the so-called Paris Agreement.

But Abbott, who was ousted by moderate Turnbull in a Liberal party coup three years ago and once declared climate change "absolute crap", has since railed against the committment he made.

He has argued it should not be enshrined in law as part of the government's new energy policy, known as the National Energy Guarantee (NEG), as consumers complain about soaring electricity prices.

"As long as we are in it (Paris) we will be running our power system to reduce emissions, not to give us affordable, reliable power," Abbott, now a vocal backbencher, said on Monday.

Several right-wingers allied to Abbott had threatened to vote with the opposition to block the NEG, and with the government only having a wafer-thin parliamentary majority, it was doomed in its current form.

Turnbull admitted there was not enough support for the Bill as he ditched plans to try to legislate the targets - an embarrassing U-turn to a key element of his signature policy.

"We are parties to the Paris agreement and the government has committed to that, but the simple reality is that we need to have effectively all of our members in the House of Representatives to vote with the government to carry legislation," he said.

"At this stage, we don't have that."

The backdown does not mean Australia has abandoned its commitment to the UN climate agreement, only that it has postponed indefinitely any attempt to make the target enforceable through law.

But closing ageing coal-fired power stations and a troubled transition to clean energy has seen power bills soar.

Internal disunity over the issue came to a head at the weekend with rampant speculation that Home Affairs Minister Peter Dutton could challenge Turnbull for the Liberal leadership, a move he denied.

"Peter Dutton was at our leadership group meeting this morning and he was at the Cabinet last night. He's a member of our team. He's given me his absolute support," Turnbull said.

A widely watched poll on Monday shows support for Turnbull has crashed to its lowest level since December.

The Ipsos poll published in Fairfax newspapers shows that although Turnbull is still personally more popular than opposition Labor leader, Bill Shorten, support for his Liberal-National coalition fell four points to 45 per cent, 10 points behind Labor and enough for a crushing electoral defeat.

Turnbull's move may relieve immediate pressure, though internal peace is seen as fragile as the government's re-election prospects look dim.

National elections are due by mid-May next year.