Foreign Minister Julie Bishop says the international agreement on climate change currently being drafted at a meeting in Paris is "about 80 per cent there" with less than 24 hours to go.

Key points: With one day left on the official schedule, climate talks remain on knife-edge

With one day left on the official schedule, climate talks remain on knife-edge Ms Bishop remains hopeful of reaching an "ambitious" agreement

Ms Bishop remains hopeful of reaching an "ambitious" agreement But the foreign minister said there were still some deals that "could go either way"

Representatives from 197 countries have been meeting in the French capital for the past two weeks to negotiate the fine detail of a treaty aimed at slowing global warming.

Despite praise for the organisation of the meeting, the talks appear to be on a knife-edge with just one day left on the official schedule.

Ms Bishop is heading a team of 46 Australians at the talks and said she remained hopeful that an agreement would be secured.

"There's a lot of work still to be done, particularly on the issue of climate finance and on the issue of the developing-developed country divide," she said.

"Essentially we want to secure an agreement that is ambitious, and ambition is captured by creating a framework for all countries to take action by ensuring transparency in the system and also ensuring that there are regular synchronised five-yearly reviews."

But she said the goodwill displayed at the beginning of the talks had carried through until the final hours, providing impetus for an agreement to be brokered.

"I think that the text is about 80 per cent there," she said.

"There are still a number of options that could go either way, but this is more positive than some were expecting."

French foreign minister Laurent Fabius, who is the president of the talks, insisted that they would not be allowed to run overtime.

He released the latest draft of the text at 9:00pm local time on Thursday night, six hours overdue.

"We are extremely close to the finish line," Mr Fabius said.

"It is time to come to an agreement. What is important now is to seek landing zones and compromise."

Ms Bishop said she was confident any agreement would be in Australia's national interest.

"There are some differing positions but compromises will have to be made and overall people don't want this to be another Copenhagen. There is a sense of optimism," she said.

At the meeting in Copenhagen in 2009, high expectations that a meaningful treaty could be reached were dashed in the final days.

Since then, incremental progress has been made at the annual gathering, first with the inclusion of 2 degrees Celsius as the accepted limit for global warming, and later with nations agreeing that a treaty should be in place by 2020.

Paris is seen to be the last chance to broker that treaty.

Negotiators are literally working day and night on the text, with informal meetings running at all hours.

The planned accord would seek to revolutionise the world's energy system by cutting back or potentially eliminating the use of greenhouse gas culprits coal, oil and gas; replacing them with renewables such as solar.

How much rich nations contribute remains a sticking point

One of the biggest potential deal-busters remaining is over money.

Rich countries promised six years ago in Copenhagen to muster US$100 billion a year from 2020 to help developing nations make the costly shift to clean energy, and to cope with the impact of global warming.

Ms Bishop said there was a sense of optimism at the Paris climate talks. ( Twitter: Julie Bishop )

But how the pledged funds will be raised still remains unclear — and developing countries are pushing for a promise to ramp up the money in future.

Another flashpoint issue is how to compensate developing nations that will be worst hit by climate change but are least to blame for it.

The developing nations are demanding "loss and damage" provisions, which the US is particularly wary of as it fears they could make US companies vulnerable to legal challenges for compensation.

Most nations submitted their voluntary plans to curb greenhouse gas emissions from 2020 in advance, a process that was widely hailed as an important platform for success.

But scientists say that, even if the cuts were fulfilled, they would still put Earth on track for warming of at least 2.7 degrees Celsius.

Negotiators remain divided in Paris over when and how often to review national plans so that they can be "scaled up" with pledges for deeper emissions cuts.

Climate experts hope clean energy sources will eventually be cheaper than fossil fuels.

Another battleground is what cap on global warming to enshrine in the accord, set to take effect in 2020.

Many nations vulnerable to climate change want to limit warming to no more than 1.5C compared with pre-Industrial Revolution levels.

However several big polluters, such as China and India, prefer a ceiling of 2C, which would allow them to burn fossil fuels for longer.

There was growing confidence within the vulnerable-nation bloc that they would win their high-profile campaign, and secure a reference to the 1.5C target in the key "purpose" section of the planned accord.

This was partly due to the emergence of an informal new lobby group that emerged this week in Paris dubbed the "High Ambition Coalition", which includes the US, the European Union and many vulnerable nations.

The group does not negotiate as a bloc, but is seen as having influenced the talks by heavily promoting "ambitious" benchmarks in the planned accord, such as a 1.5C reference.

ABC/AFP