A draft joint declaration being negotiated by the United States and Pacific Island countries condemns Russia's invasion of Ukraine, flags intensifying American security cooperation with the region and declares climate change is the "highest priority" and "single greatest existential threat" to the Pacific.

The joint statement being negotiated by the US and the Pacific for the summit spans a wide range of topics, including climate change, security, illegal fishing, the legacy of nuclear testing and the economic recovery from COVID-19.

Solomon Islands signals it won't sign on to this week's 11-point declaration negotiated by the United States and Pacific Island nations.

The declaration opens by saying the US and Pacific Island countries "recommit to working together in genuine partnership" to tackle "mounting challenges" including a "worsening climate crisis and an increasing complex geopolitical environment.".

The senior official also declined to comment directly on the decision by Solomon Islands not to join the declaration, saying simply that the US was "patient and fully committed to working in close consultation with Pacific Island nations on the issues that we both think are critical going forward."

"The draft declaration is revealing in what it tells us about the constraints and limits of US engagement and action as well as the clear position that Pacific countries are taking with respect to Forum centrality and their' red lines' when it comes to climate change and the sovereignty and national interest of member states," she said