A group of Pacific island nations is aiming to make shipping in the region carbon-neutral by 2050.

The Pacific Blue Shipping Partnership, involving Fiji, the Marshall Islands, Samoa, Vanuatu, the Solomon Islands and Tuvalu, hopes to raise $500m through "blue bonds" to meet the target, The Guardian reported.

The money will also come from grants, banks and private sector investment.

It will go on retrofitting existing passenger and cargo ferries, and ordering new zero-emissions vessels.

The group's initial aim is to cut emissions by 40% by 2030.

The countries are very dependent on imported fossil fuels and therefore more at risk from price shocks or disruptions to supply.