Fiji on Monday challenged Australia to do more on climate change ahead of a regional summit of Pacific nations this week, warning Canberra's reliance on coal posed an "existential threat" to low-lying islands.
Prime Minister Frank Bainimarama said Australia should recognise the threat climate change poses to Pacific island nations.
"I appeal to Australia to do everything possible to achieve a rapid transition from coal to energy sources that do not contribute to climate change," he told a function in Tuvalu, which will this week hold the annual Pacific Islands Forum.
Some low-lying Pacific island nations are threatened by rising seas, while others are pummelled by cyclones that have become more regular and powerful due to climate change.
There has been disquiet in the Pacific that Australia -- led by climate-sceptic Prime Minister Scott Morrison -- recently approved the giant Adani coal mine in Queensland state.
"We face an existential threat that you don't face and challenges we expect your governments and people to more fully appreciate," Bainimarama said.
He added: "Put simply, the case for coal as an energy source cannot continue to be made if every nation is to meet the net zero emission target by 2050."