Australian Pacific cyclone aid welcomed, 'more needed'

Australia has made a "small but vital" pledge of humanitarian support for two Pacific neighbours after a tropical cyclone triggered severe flooding and landslides, killing at least 11 people.

Cyclone Maila tore through communities, destroying homes, roads and bridges as it tracked across parts of Papua New Guinea and the Solomon Islands last week and across the weekend.

Four children are reportedly among the people killed in PNG, and the Solomon Islands government has declared a state of disaster in two provinces.

Save the Children Australia Pacific regional director Kim Koch said many people were without food, water and shelter, but a clear picture of Maila's full impact was still emerging.

"We haven't been able to send boats out to all of the islands," she told AAP on Monday.

"It's quite remote, some of these areas, and the rain is still coming, so we're struggling."

The federal government will provide an initial $1.5 million to the Solomon Islands, where the most severe impacts from Maila have been felt in remote communities.

A further $1 million will help PNG respond to humanitarian needs in areas impacted by the cyclone, including the Autonomous Region of Bougainville and islands in Milne Bay Province.

The Australian Council for International Development said it was deeply concerned about the cyclone's ongoing impacts, and the funding was a "small, but vital, contribution".

"People in the region are being severely impacted by strong winds, heavy flooding, and damage to infrastructure and roads," chief executive Matthew Maury said.

"It is clear further contributions will be needed as communities seek to rebuild as this crisis continues to unfold."

The impacted region comprises hundreds of small islands, where many people live in isolated communities.

"Really hard to reach areas in conditions that remain super volatile," Ms Koch said.

"Taking small boats full of supplies out onto a rough sea, it's just not ideal and safe. It's really rough going."

Water and food supplies are the immediate need.

"We have reports from the Solomon Islands that a lot of water sources in coastal communities have been salinated," Ms Koch said.

"Eventually, the lack of clean water available will start to lead to disease and nutrition issues.

"Getting that assessment, getting that assistance out there quickly, is critical."

Save the Children is among the aid organisations on the ground. It is delivering hygiene and shelter kits, and cash payments to impacted families in Bougainville.

"In the Solomon Islands, we have been able to distribute food to some of the evacuation centres and have been able to start up some child-friendly spaces to give kids a safe play area," Ms Koch said.