Six Arab countries including Saudi Arabia and Egypt have cut diplomatic ties with Qatar, accusing it of destabilising the region.
They say Qatar backs militant groups including so-called Islamic State (IS) and al-Qaeda, which Qatar denies.
The Saudi state news agency SPA said Riyadh had closed its borders, severing land, sea and air contact with the tiny peninsula of oil-rich Qatar.
The unprecedented move is seen as a major split between powerful Gulf countries, who are also close US allies.
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