The Marshall Islands is seeking $26 million in aid money to help build about five kilometres of sea wall to protect the capital, Majuro.
Virtually all of the Marshall Islands is a little more than a metre above the high-tide mark.
The Environment Protection Authority says the plan is to build a wall on Majuro first, before doing the same on the other populated atoll.
It says it could take up to three years to build the first wall.
