A representative of Guam's Chamorro in Diaspora group is warning that a lack of self-governance means the territory will continue to be shut out of decisions around the military build-up.
The United States has been discussing plans to transfer thousands of marines from Japan to Guam for more than six years, as part of maintaining an effective presence in the Asia-Pacific region.
But Tiara Naputi told a United Nations decolonisation committee earlier this month that the build-up continues to be negotiated in secret.
She says the renewed efforts to relocate marines from Japan to Guam risk repeating history.
"As once again the people of Guahan have been informed after the fact about discussions regarding the build up that took place behind closed doors. This lack of transparency and secrecy is one of the many by-products of Guahan's precarious political status as a non self-governing territory."
A representative of Guam's Chamorro in Diaspora group, Tiara Naputi.