Restoring the unity of Gulf nations is in the interest of all parties in the region, US Secretary of State Rex Tillerson said on Tuesday. He also urged them to resolve a diplomatic dispute over Qatar. Tillerson made the statement at a meeting in Kuwait of the global coalition against Islamic State (IS, formerly ISIS). Last June, Saudi Arabia, Egypt, the United Arab Emirates and Bahrain severed ties with Qatar, accusing it of supporting terrorism, a move opening up the worst rift in years among the US allies. Qatar denies the accusation.