United States Congressional leaders want to restrict the flow of Micronesians to the US.
In a letter, they say the high cost of providing social services to the thousands who have migrated has made the open door policy unsustainable.
The group of nine members of the U.S. Senate and House of Representatives and the chairman of a key oversight committee for the islands, directed the letter to the U.S. Secretary of State and the Secretary of Interior.
The group want to reach agreement with island governments to set up screening procedures to limit the number of incoming islanders from Marshall Islands, Micronesia and Palau.
The Marshall Islands Foreign Minister, John Silk, expressed his concern at the move, saying locals will object to any system that imposes a de facto visa requirement.
He says this is the first time since "compacts of free association" were approved in 1986 and renewed in 2003 that U.S. officials have sought to restrict unfettered flow of islanders into the U.S.
Estimates of Micronesians and Marshall Islanders living in the U.S. range from 30,000 to 40,000.
The letter was also issued two days after an agreement was signed by Marshall Islands landowners cementing use of the Kwajalein missile testing range by the U.S. Defence Department through to 2066.