Solomon Islands foreign affairs ministry permanent secretary, Collin Beck, says some tough talks need to be had around the inclusion of non-independent countries in the Pacific Islands Forum (PIF).
Beck said associate and full membership status of the largest regional body was originally set up for independent countries only - to meet international law and the UN Charter.
New Caledonia became a full member in 2016 on the basis that they were undergoing decolonisation.
Questions have been raised over Guam and American Samoa's bids for associate membership given they are US territories, set to be decided on Friday by PIF leaders.
Guam's Governor Lou Leon Guerrero has told RNZ Pacific: "I want to be a full member of PIF. That's my goal."
Griffith Asia Institute's Pacific Hub project lead, Dr Tess Newton Cain, has said "being able to have two of its territories, American Samoa and Guam, get that associate membership - if that happens - does seem to indicate this is how [US] get a little bit of an edge on China."
Beck told journalists in Nuku'alofa this week that these were issues which are being looked into by leaders.
"For the region, I think when we look at the regional architecture, there are these are things that we will be discussing," he told RNZ Pacific.
"Of course, Solomon Islands [does] have its view on it.
"We would like to ensure that we have...we start where the forum have started. Basically in 1971 it was based on sovereign self-governing countries.
"This is to ensure that the definition of intergovernmental organisation meets the international meets international law, as well as the UN Charter.
He said currently there are "a range of countries that includes non-independent countries".
"It's basically the question is, should we reform SPC [ Pacific Community] to have it speak politically so that you know you have a space in which territories will be able to learn.
A review of the regional architecture is underway but not yet completed.
'Guam needs to be on the table' - ex-US Congressman
Former Guam congressman and the Pacific Centre for Island Security, Robert Underwood, told RNZ Pacific earlier this month that Guam needs to be at the table.
"I do not believe that Guam needs to be at the table because it has necessarily something to offer the others. I think Guam needs to be at the table so that they can understand the fulfillment of their own potential as a player in the Pacific."
But he said most people on Guam do not see it that way.
He said that is why Guam's pitch for PIF associate membership is critical.
"Sometimes there are people in Guam who will say, 'well, [PIF] should let us in because we have a lot to offer them'.
"But I always say we should get in because they have a lot to offer us. They have a lot to offer us in terms of perspectives and to become fully engaged in all the activities that you have.
"There is a little bit of shuffling around that is done by the by the pit. They talk about the Blue Pacific, and they talk about doing all these fantastic things for the Blue Pacific, but they do not include everybody in the Blue Pacific."
Underwood believes the PIF uses various scenarios as to why that US territories cannot be included in the regional body.
"It's hard to imagine that Guam, Commonwealth of Northern Marianas and American Samoa, are joining to be kind of a subterfuge for the US as additional voices," he said.
"They may be confused for a while, but I think over time, they will become aware of their own capacity and their own agency."
He added associate membership would be not just good for the region but invigorating for Guam.