His predecessor Malcolm Turnbull planned to attend the forum in Nauru, but those plans were abandoned when he was thrown out of the top job last week.

Mr Morrison, who has travelled to Indonesia for his first overseas trip in the role, has decided not to continue on to Nauru.

Newly-minted Foreign Minister Marise Payne will be dispatched to the tiny island nation instead.

Mr Morrison is confident Pacific leaders will understand his absence.

"We are going back to parliament the following week, I have some very pressing matters as a new prime minister I have to deal within my own country," he told reporters in Jakarta on Friday.

"Those in particular are the issues of drought. There's the critical issue of getting electricity prices down.

"There's a lot of work to do in a short period of time before we get back to parliament in just over a week's time."

Mr Morrison said in ordinary circumstances he would love to be at the forum, as he counts Pacific leaders as family.

"It is an unusual set of circumstances and I am sure that my colleagues in the Pacific Islands Forum will be very understanding," he said.

"But I suspect they'll tease me next time I see them and have a bit of a joke at my expense."

Australian Associated Press