The US Ambassador to Samoa, David Huebner, and the Prime Minister, Tuilaepa Sailele Malielegaoi, have signed a bilateral Shiprider Agreement.
The move enables Samoa's law enforcement officials to help enforce regulations governing fisheries and other maritime laws on US Coast Guards ships.
The agreement was signed on the second day of celebrations of Samoa's independence golden jubilee.
The US Ambassador says the deal will also advance Samoa's economic and security interests as well as deepen the cooperation between the US and Samoa.
The agreement applies to uniformed members of the U.S. Coast Guard and members of the Samoan Ministry of Police and Prison, as well as authorised officers of the Ministry of Agriculture and Fisheries.