US President Donald Trump threw his weight behind efforts to isolate Qatar on Tuesday, backing Saudi Arabia and its allies after they cut ties with Doha over claims it supports extremism.
In a surprise move against a key US ally, Trump suggested Qatar -- home to the largest American airbase in the Middle East -- was funding extremism as he tacitly backed the diplomatic blockade of the emirate.
"So good to see the Saudi Arabia visit with the King and 50 countries already paying off," Trump said in a morning tweet, in reference to his trip to Riyadh last month.
"They said they would take a hard line on funding... extremism, and all reference was pointing to Qatar. Perhaps this will be the beginning of the end to the horror of terrorism!"
Trump's broadside came as Kuwait's ruler flew to Saudi Arabia in a bid to resolve the worst diplomatic crisis to hit the Arab world in years.
Saudi Arabia and allies including Egypt, the United Arab Emirates and Bahrain announced Monday they were severing diplomatic relations and closing air, sea and land links with Qatar.
They accused the tiny Gulf state of harbouring extremist groups and suggested Qatari support for the agenda of Saudi Arabia's regional arch-rival Iran.
Energy-rich Qatar has long had strained ties with its neighbours but the move by Riyadh and its supporters shocked observers, raising fears the crisis could destabilise an already volatile region.
The dispute comes less than a month after Trump visited Saudi Arabia and called for Muslim nations to unite against extremism.
The rift was already having tangible effects, with dozens of flights cancelled, Qatari planes barred from regional airspace, and panic buying in Doha amid fears of food shortages.
Kuwait did not join fellow Gulf countries in taking measures against Doha, and its Emir Sheikh Sabah al-Ahmad Al-Sabah arrived in the Saudi city of Jeddah for talks to resolve the crisis.
In a call with Sheikh Sabah on Monday, Qatari leader Sheikh Tamim bin Hamad Al-Thani had agreed to put off a speech to the nation in order to give mediation a chance.