When statements don’t make sense, i find it helpful to cut out any part that offends logic and see if it becomes clearer. In this case i apply it like this:
“[T]he United States has made clear that it will block Palestinian membership and statehood.
There! The other parts were extraenous fluff to soften their perceived position.
(I know you already grok their position, I’m just sayin its a hack i like.)