The United Nations General Assembly has adopted its first declaration specifically addressing the growing threat of sea level rise, affirming that island countries do not automatically lose their statehood even if rising seas submerge parts of their territory.
The four page declaration, adopted on September 24, 2026, also supports maintaining established maritime zones despite changes to coastlines caused by rising seas. The move is particularly significant for small island nations such as Tuvalu and the Marshall Islands, which face increasing risks from coastal flooding and land loss.
The declaration calls for stronger climate adaptation measures including early warning systems, coastal protection and greater financial and technical support for vulnerable developing countries.
According to the UN global mean sea level reached a record high in 2024 after rising by 5.9 millimetres that year driven largely by exceptional ocean warming. Around 770 million people worldwide live less than five metres above the high tide line.
The UN also highlighted nature based solutions such as restoring mangroves, kelp forests and seagrass meadows, along with incorporating sea level projections into the planning of ports transport networks, energy systems and other critical infrastructure.
Small island nations welcomed the declaration but stressed that adaptation alone cannot stop rising seas. They have called for stronger action to reduce greenhouse gas emissions and limit further global warming.