U.S. Republican presidential candidate Mitt Romney has won his party's nomination contest in the U.S. territory of Guam, U.S. media reported Friday.

Romney won unanimous backing at the convention, with all Republicans who attended the conference supporting him. Local newspaper Pacific Daily News quoted convention co-chairman Victor Cruz as saying 251 delegates were to participate in the convention.

The territory has only 9 delegates. The time was already Saturday morning at Guam when the voting took place, when U.S. mainland was still on Friday.

Romney's son Matt attended the Guam convention. Matt Romney also visited neighboring Northern Mariana Islands. Republicans there are set to vote there this weekend.