The problem must be addressed “in a legal and human rights framework”, Guterres warned.
He added that rising sea levels mean land shrinking, which could lead to potential disputes over land and sea space.
“The current legal regime must look to the future and address any gaps in the current framework,” including international refugee law, he added.
It should also provide for the future of states that face losing their land area entirely.
Guterres said the Security Council has a “pivotal” role to play in tackling the “catastrophic security challenges posed by rising sea levels”.
The issue has been controversial in the past: In 2021, Russia vetoed a resolution linking climate change and global security, which was supported by a majority of the council members.