The Marshallese Government has called on Australia to support its new global climate change initiative.

The Marshall Islands is hosting this year's meeting of the 16-nation Pacific Islands Forum in September.

It wants leaders to agree to approve the Majuro Declaration for Climate Leadership, an initiative for urgent action on climate change.

Tony de Brum, the Minister in Assistance to the Marshall Islands President, is in Canberra to highlight the unprecedented droughts and floods that have hit his country and to seek support from the Australian Government ahead of the Pacific summit.

He says Australia is crucial to the success of the Majuro Declaration, especially with its new role on the United Nations Security Council.

"We think that anything that the Pacific Islands do in terms of climate change must have the blessing, the support and the voice of Australia and New Zealand to the outside world," he said.

"You have circles of diplomatic friends far wider and much more powerful than each of us, or even of the small island states of the Pacific put together.

"Those important connections must be used to draw attention to the fact that climate change is now, it needs the attention of the world now, and the sacrifice of the large developed countries must be part of that solution."

Senator de Brum warns rising sea levels will create a humanitarian crisis in the region, with many people eventually seeking asylum in Australia.

"If you look further down the line there are two million people - potential refugees - from the Pacific should climate change continue the way it is now, and that will be an overwhelming problem."