A ship sails off the coast of Ajman. AFP
"The main purpose of the visit is reportedly to try to reinforce Qatar's role as a mediator following events on Tuesday," Tasnim news agency reported, after Doha accused Iran of an attack on an LNG carrier, with two other tankers also hit in the strait.
On Wednesday, US President Donald Trump said the ceasefire with Iran was "over" after the two sides traded fire, but added that negotiators could keep talking to Tehran.
In parallel, the United States launched extensive strikes on Iran over attacks on ships in the vital Strait of Hormuz, triggering a wave of reprisals Wednesday that Iran's Guards said targeted US bases in the Gulf.
Both sides reported hitting dozens of targets in renewed hostilities, which have placed fresh strain on an interim deal to end the Middle East war and pushed oil prices to their highest level in two weeks.
Washington revoked sanction waivers on Iranian oil sales and launched the new attacks on military sites in what the US military called retaliation for Iran's strikes on three commercial ships in Hormuz.
Iranian state media reported a wave of explosions around the strait, including six on the island of Qeshm, seven in the city of Sirik and more in the major port city of Bandar Abbas.
This followed a Tuesday report from British maritime security agency UKMTO, which said
an "unknown projectile" hit a tanker near Hormuz, causing a fire, before two more vessels were struck, at least one by a drone.
CENTCOM identified the ships as the Marshall Islands-flagged Al Rekayyat, the Saudi Arabia-flagged Wedyan and the Liberia-flagged Cyprus Prosperity.
Maritime traffic had tentatively resumed after Washington and Tehran signed the memorandum last month to end the war that started in February.
Under the 14-point US-Iran memorandum, declared over by Trump, Iran and Oman, which border Hormuz, must hold talks "to define the future administration and maritime services" in the waterway with other Gulf states.
Qatar had previously refused to mediate under Iranian fire as Tehran launched an unprecedented aerial bombardment against Gulf states in retaliation for the US-Israeli strikes.
But Doha has since taken a more active role, hosting indirect talks between Iran and the United States last week.
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