Fiji's Prime Minister has hit back at a Liberal MP who suggested Pacific Islanders should move to higher ground to avoid the impacts of climate change.

Key points: Frank Bainimarama said John Alexander's advice would be "useless" for low-lying nations

Frank Bainimarama said John Alexander's advice would be "useless" for low-lying nations He said Australia had a moral responsibility to fight climate change

He said Australia had a moral responsibility to fight climate change He also lashed out at Kevin Rudd's "insensitive" climate change suggestions

John Alexander stoked controversy at a candidate's forum when he said Australia's response to climate change should focus on helping Pacific Island nations to build more resilience to severe weather, including by removing low-lying dwellings.

But Frank Bainimarama said Pacific Islanders would find it wrenching to abandon their homes, and Mr Alexander's solution would be useless for tiny Pacific nations which barely rise above sea level.

"I do feel entitled to give a return serve to a former tennis great, turned politician, who mentioned me by name at an election meeting a couple of days ago," Mr Bainimarama told a climate change conference in Melbourne.

"Despite the enormous difficulties of these decisions, Fiji is lucky we even have the higher ground to allow for relocation at all.

"I'm keen to hear what the honourable member believes the people of Kiribati should do in the face of rising seas, when the highest point in their country sits at just 1.8 metres above sea level."

Fiji's Prime Minister said developed countries like Australia had a moral responsibility to fight climate change by cutting their carbon emissions.

Mr Bainimarama said Pacific Islanders would find it wrenching to abandon their homes. ( Supplied: Darren James )

And he lashed out at former Prime Minister Kevin Rudd, who suggested that some small low-lying Pacific nations threatened by climate change could trade their sovereignty in return for Australian citizenship

"In a time when we must be future-facing we can hardly tolerate such insensitive, neo-colonial prescriptions," he said.

"I implore leaders of Australia to visit these communities and see them firsthand before they propose solutions that are so blatantly out of touch with the reality that Pacific Islanders live with on the ground, day in and day out."

Pacific nations are preparing to mount a renewed push on climate change ahead of a crucial UN summit in September.

Next week, UN secretary-general Antonio Guterres will travel to the Pacific as he tries to build broader global support for deeper cuts to emissions by major polluters.

Mr Bainimarama said it wasn't clear if the world could muster the political will stop global warming. ( Oxfam: Rodney Dekker )

Mr Guterres and Pacific leaders will hold a major summit to discuss climate change and call for global action.

Frank Bainimarama said it still wasn't clear if the world could muster the political will to stop "catastrophic" global warming, which was already damaging Pacific nations as storms and cyclones intensified.

"Let's be clear, the costs of climate change to our industries, our people, our potential, are crippling," he said.

"This climate crisis kills. [It] destroys the lands we love."