"We are all not happy. And disappointed it's ended up like this," Foreign Minister Justin Tkatchenko told AFP after Australia ceded hosting rights to Turkey.

Australia had been pushing to host COP31 next year alongside South Pacific nations which are increasingly threatened by rising seas and climate-fuelled disasters.

But Australia pulled the plug on its long-touted bid after Turkey, the other prospective host, refused to back down.

It would have been the first time the region had hosted the UN's premier climate summit.

Tkatchenko on Thursday lashed the entire COP summit process as a waste of time.

"What has COP achieved over the years. Nothing," said Papua New Guinea's top diplomat.

"It's just a talk fest and doesn't hold the big polluters accountable."

Australia started walking back its bid earlier this week as leaders met in the Brazilian port city of Belem.

Prime Minister Anthony Albanese pledged that, if Australia did lose out, he would still look for ways to keep the Pacific's plight on the agenda.