Foreign Minister Julie Bishop has defended the government on multiple fronts over the Paris climate change talks amid criticism from the backbench.

Prime Minister Malcolm Turnbull told leaders at the meeting Australia would make cuts of between 26 per cent to 28 per cent by 2030 as part of a global effort to reduce carbon emissions.

He also flagged increasing the target when a review is conducted in five years’ time.

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But Liberal MP Dennis Jensen said the Prime Minister should stick with the position of the party room.

The backbencher said discussion about increasing the target was “a joke”.

“I will certainly be very strong on the fact that we should not change those targets and that we stick with what we agreed [in] the partyroom and we don’t change,” he said.

“If there’s discussion about it a couple of years’ in the future, don’t change it again.”

Ms Bishop said the government would not be renegotiating its target at the Paris talks, but has kept the option open of reviewing it in 2020.

“It was agreed to by our party room, it is the mandate I have in Paris, so we’re not looking to renegotiate,” she said.

“There is no room for renegotiation … but in five years’ time we can review where we’re up to. If our past history is anything to go by, we over-achieve, we exceed our targets.”

Acting Opposition Leader Tanya Plibersek said it was a sign of fresh divisions within the Federal Government.

Ms Plibersek said Mr Turnbull had “well and truly scared the horses”.

“You see backbenchers out, already repudiating the Prime Minister for even the modest announcement that he’s made,” she said.

“Even the damp squib in Paris is causing all sorts of problems at home, we’ve had to see the foreign minister running around this morning saying, ‘nothing to see here, nothing new’.”

Turnbull pledges $1 billon to fight climate crisis

Mr Turnbull pledged $1 billion over the next five years for the Green Climate Fund, including an initial $200 million promised earlier this year.

It will be used to help Pacific Island nations deal with the threat of rising sea levels, but there will not be any new money — instead it will be funded out of the existing foreign aid budget.

Ms Bishop said it was an appropriate way to pay for the scheme.

“This is what the aid budget is designed to do, to assist in natural disaster relief, to build resilience against natural disasters,” she said.

“Indeed, this is what the small island developing nations of the Pacific are asking for.”

Ms Plibersek has criticised the plan, stating “this is pretty rich, considering we have actually cut funding to countries like Kiribati that are currently struggling with climate change adaptation and mitigation, in fact we cut $2.5 million from Kiribati.”

Greens Leader Richard Di Natale was also scathing of the decision, claiming Mr Turnbull’s announcement in Paris has been a “huge disappointment”.

“He has not committed one extra cent to climate financing, in fact he’s taken money out of the aid budget,” he said.

“This is a shameful exercise here. We have Malcolm Turnbull talking a big game, and failing to deliver.”

Government will not sign communique

The Federal Government will not sign up to a communique at the Paris meeting calling for a reduction in fossil fuel subsidies, in a move welcomed by the Nationals.

There were fears the communique would jeopardise the multi-billion dollar diesel fuel rebate, which subsidises the off-road use of fuel by farmers and miners.

Nationals Deputy leader Barnaby Joyce said it was a “win for common sense”, though the move prompted criticism from the Opposition.

Ms Plibersek has criticised Mr Turnbull, claiming the Nationals have “yanked the chain” to bring the Prime Minister into line.

She confirmed Labor had “no plans” to change the diesel fuel rebate.

Ms Bishop said she had worries about the communique when the issue was discussed last week.

“There were some paragraphs in the proposal from New Zealand that caused us some concerns and they couldn’t be negotiated in time so we didn’t sign up for it,” she said.