French President Emmanuel Macron has issued a challenge to Australia to lift its game when it comes to tackling climate change.

Key points: Mr Macron spoke of his concern about the effect of climate change on Pacific nations

Mr Macron spoke of his concern about the effect of climate change on Pacific nations France has deep interests in the Pacific, forged through decades of colonialism

France has deep interests in the Pacific, forged through decades of colonialism New Caledonia will hold a referendum later this year on whether to break away from France

Mr Macron, who arrived in Sydney last night, is only the second sitting French President to make an official trip to Australia.

The first stop on his whistle-stop tour was a dinner at the Sydney Opera House joined by politicians, business leaders and French expats.

During his speech, the President called on Prime Minister Malcolm Turnbull to show the "power of conviction" and display courage in confronting climate change, despite the ideological hurdles he may face in both the Parliament and his party room.

"I am fully aware of the political and economic debate surrounding this issue in your country, and I respect this," Mr Macron said.

"But I think that actual leaders are those that can respect those existing interests, but at the same time decide to participate to something broader, to something more strategic."

France has deep interests in the Pacific. ( AP: Mick Tsikas/Pool Photo )

In launching the plea, Mr Macron suggested some of Australia's closest neighbours feel the effect of climate change more acutely than others.

"When I speak about vulnerability, I want to speak obviously about climate, which is an absolute priority," Mr Macron said.

"Numerous states in the Pacific are at direct risk of disappearing completely in only a few years if we do not take action.

"How could this life be better if we decide to sacrifice the life of our children? It is not an option."

France has deep interests in the Pacific, forged through decades of colonialism.

Mr Macron will travel to New Caledonia after his trip to Australia.

The country will hold a referendum later this year on whether to break away from France.

'You are a man who is for, not against'

Mr Turnbull and Mr Macron are also expected unveil new agreements to boost military co-operation and deepen collaboration on cyber security.

They will also discuss China's growing strategic presence in the Pacific and the possible collapse of the Iran nuclear deal.

US President Donald Trump has vowed to tear up the deal, which lifts sanctions on Iran in return for Tehran curtailing its nuclear weapons program.

Mr Macron has been urging Mr Trump to change his mind, warning that junking the agreement would be deeply destabilising.

Australia has also been pressing the US not to abandon the deal — but it has been much less forceful in its advocacy than France.

Mr Turnbull also heaped praise on Mr Macron at last night's dinner, paying tribute to his vitality and ambition.

"You are a man who is for, not against," Mr Turnbull said.

"We might say 'always on the front foot, always a glass half full, not half empty'."