Qatar's premier attended an annual Gulf Cooperation Council (GCC) summit in Saudi Arabia on Tuesday, its highest representation since 2017, but there was no public mention of the two and half year boycott by its neighbours despite hints of a thaw.
Prime Minister Sheikh Abdullah bin Nasser Al Thani's presence follows an intensification of efforts to resolve the row among US allies which shattered the GCC alliance amid growing Iran tensions.
Saudi Arabia, the United Arab Emirates, Bahrain and non-GCC member Egypt cut diplomatic and trade ties with Qatar in June 2017 over allegations that it backs terrorism. Doha denies that and accuses them of trying to curtail its sovereignty.
Kuwait and the United States have tried to mediate the rift which undermined Washington's efforts to form a united front against Iran, which is locked in a struggle for regional supremacy with Saudi Arabia.
A senior regional official told Reuters that Kuwait recently was working "extremely hard to come up with reconciliation… supported by the United States".
Efforts to end the row, including unannounced Qatari-Saudi talks in October, appeared to intensify after attacks in September on Saudi oil plants that initially halved the kingdom's output and pushed the region towards war.
Riyadh and Washington blame Iran for the assault along with earlier strikes this year on tankers in Gulf waters. Tehran denies involvement.
Saudi King Salman, who afforded the Qatari prime minister a traditional welcome on Tuesday, called for regional unity to confront Iran and secure energy supplies and maritime channels.