The President of the Marshall Islands has questioned Australia's standing in the Pacific over its inaction on climate change.

Dr Hilda Heine delivered this year's ST Lee Lecture at the Australian National University in Canberra on the topic "Climate Change Crisis".

Sorry, this audio has expired President Hilda Heine calls on Australia to support Marshall Islands climate change struggle ( James Fettes )

"It is hard to explain the feeling of being the President of a country reading a report that supposedly condemns your country to oblivion," she said.

Dr Heine said Australia is risking its reputation as the world looks to reduce carbon emissions.

"Now is not the time to be debating the science, trashing solar power, or building new coal mines," she said.

"I can assure you it does influence the way Australia is viewed in the Pacific."

Dr Heine also took aim at Australia's freezing of its foreign aid budget, comparing the country to an older sibling bullying its younger brothers and sisters.

"Imagine how you'd feel if your big brother or big sister was not only openly mocking the science but even occasionally mocking your very own plight," Dr Heine said.

"This not only does your country disservice, it openly weakens your ability to be a force for good on the world stage."

Paris Climate Accord 'last chance for the world'

The Marshall Islands has been a fierce defender of the Paris Climate Accord, which it says is critical to the very survival of the island nation.

US President Donald Trump is considering whether to withdraw from that agreement; something Dr Heine said would have serious consequences.

"Paris is the last chance for the world. We must hope the President sees that strong international cooperation based on climate science is the way to avert the catastrophic threat to our very existence," she said.

Dr Heine said the Marshallese people have already been displaced once, during Cold War-era US nuclear testing, and would do all they could to stop that happening again.

"It may well be too late for my country, but we simply do not know that yet. My country will not stand down from this fight and nor will my people," she said.

"We refuse to be the so-called climate refugees."