Australia will sign up to the next phase of the Kyoto Protocol on cutting greenhouse gas emissions, despite concerns from some environmentalists that carbon reduction targets remain too low.

The current agreement is due to expire this year, although agreement on a new globally-binding deal is not expected until 2015.

Climate Change Minister Greg Combet has announced that Australia is willing to sign up to the next phase of the Kyoto agreement, which will effectively act as a bridging deal until a new long-term plan can be agreed to.

In making the announcement at a carbon expo conference in Melbourne, Mr Combet declared this commitment would not be a blank cheque and it would come with certain conditions.

"For Australia, there must be continued progress towards this new agreement by 2015, from both the developing and developed countries alike," he said.

"The Kyoto Protocol is not enough on its own - it will cover less than 15 per cent of global greenhouse gas emissions and only from a number of developed economies.

"So to be effective, the new 2015 agreement needs to cover all the major emissions sources."

Talks aimed at finalising a second commitment period for the Kyoto Protocol are due to begin in Doha later this month, as international leaders work towards a 2015 deal that is not expected to come into force until 2020.

As part of the 'Kyoto 2' deal, Mr Combet says Australia will sign up to the bipartisan 5 per cent target for cutting carbon emissions by 2020 based on 2000 levels, with the prospect of increasing that commitment to up to 25 per cent if there is stronger global action.

Higher targets

While Greens leader Christine Milne is pleased the Government will sign up to the next phase of Kyoto, she remains concerned about the level of ambition in cutting emissions.

"We should be in the 25 to 40 per cent reduction space because that's what the Bali road map had said that developed countries like ours should achieve," Senator Milne told ABC News.

"Whatever Australia commits to, it has to be able to achieve a much greater level of ambition."

The Climate Institute is optimistic that Australia's eventual 2020 target will be at the upper end of the Government's commitment.

"Clearly, the level of action that is happening internationally is significant, and that would indicate that the level of ambition that all countries should be taking should be increased," the Institute's Erwin Jackson told reporters in Melbourne.

Australia has now become the first developed country outside of Europe to pledge its support for an extension to the Kyoto agreement, something the British government says will help momentum for a new global deal.

"Having Australia on board will really help to push the second Kyoto Protocol period which is vital to maintaining agreed rules to cut global emissions as we make the transition to a new, global, legally binding deal," said British secretary of state for energy and climate change, Edward Davey.

"Australia's work to reduce emissions is bold and promising.

"I'll be working hard with Greg Combet and our global counterparts to make even more progress in Doha."

The original Kyoto deal was never ratified by the US because it did not impose targets on developing nations such as China and India.

Japan and Russia have already said they will not sign up to an extension of the agreement because it does not cover enough of the global greenhouse gas emissions.

By signing up to the next Kyoto phase, Australian businesses will get access to international carbon credits to help them achieve domestic targets.

Colourful language

In making today's announcement, Mr Combet lashed out at some of the claims put forward by the Coalition as part of the domestic debate around the carbon tax.

He says the prediction by Opposition Leader Tony Abbott that the tax would be like a "wrecking ball" through the economy has been proved wrong, given the continued growth of the Australian economy.

Mr Combet has accused Mr Abbott of lying and deception, and says it is no surprise voter support for the Coalition had fallen since the carbon price came into effect.

He has also challenged Mr Abbott's promise to call an early poll if he wins next year's election but is prevented by the Senate from repealing the carbon tax.

"Given everything he has said about this issue - to be frank about it and so that you don't misunderstand anything I'm saying - has been complete bulls**t, is he really going to go to a double dissolution election on this issue?" he said.

"It is important to understand that this has been purely a political strategy on Mr Abbott's part.

"It's yielded good dividends for him politically over the last 18 months, but that period is over."

Asked later about his choice of "colourful language" to describe the Opposition Leader, Mr Combet told reporters: "Mr Abbott deserves it."

Opposition Climate Change spokesman Greg Hunt hit back at Mr Combet's comments, saying the attack is a sign of Labor's desperation.

"If Labor wants a debate about honesty, then Australians will remember the phrase "there will be no carbon tax under the government I lead"," he said in a statement.

"The reality is that Australian families and businesses are angry that their power bills have gone up due to the carbon tax.

"But the Government is trying to pretend that it's not an issue having deceived the community at the last election."

Mr Abbott this morning continued his attack on the carbon tax, telling Channel Nine it was responsible for significant increases in electricity prices.

"Every time your power bill goes up, the Prime Minister has a smile on her face because that is the carbon tax just doing its job," he said, reiterating his promise to repeal the tax.

Pressed on what else he would do to bring down power prices, Mr Abbott replied: "The plan starts with getting rid of the carbon tax."

He says if Labor is serious about taking action to curb spiralling power prices, it would immediately scrap the carbon pricing scheme.