Saudi Arabia said on Monday that two Saudi oil tankers were attacked off the coast of the United Arab Emirates, condemning it as an attempt to undermine the security of crude supplies amid heightened U.S.-Iranian tensions. The UAE said on Sunday that four commercial vessels were sabotaged near Fujairah emirate, one of the world's largest bunkering hubs lying just outside the Strait of Hormuz, but did not say who was behind the attack or describe the nature of it. Iran, embroiled in an escalating war of words with the United States over sanctions and the U.S. military's presence in the region, moved on Monday to distance itself. The foreign ministry called the incidents "worrisome and dreadful" and asked for an investigation into the matter. A senior Iranian lawmaker said "saboteurs from a third country" could be behind it, after saying on Sunday that the incident showed that the security of Gulf states is fragile. In a sign of concern about rising tensions, Britain's Foreign Minister Jeremy Hunt warned of the risks of "a conflict happening by accident" with an unintended escalation between Washington and Tehran over an unraveling nuclear deal.

Saudi Arabia's Energy Minister Khalid al-Falih attends a press conference at the end of the 13th meeting of the Joint Ministerial Monitoring Committee (JMMC) of OPEC and non- OPEC countries in Baku on March 18, 2019. Mladen ANTONOV | AFP

A fifth of global oil consumption passes through the Strait from Middle East crude producers to major markets in Asia, Europe, North America and beyond. Iran's Revolutionary Guards, which has been designated a terrorist organisation by the United States, threatened last month to close the chokepoint if Tehran is barred from using it. Oil prices rose on Monday, with Brent crude futures trading up 1.1% at $71.77 a barrel. Saudi Energy Minister Khalid al-Falih said in a statement that one of the two Saudi vessels attacked was on its way to be loaded with Saudi crude from Ras Tanura port for delivery to state-owned Saudi Aramco's customers in the United States. The attack did not lead to any casualties or an oil spill but caused significant damage to the vessels' structures, he said. INTERTANKO, an association of independent tanker owners and operators, said in a note that it has seen photos showing that "at least two ships have holes in their sides due to the impact of a weapon." Trading and shipping sources identified the Saudi vessels as Bahri-owned very large crude carrier (VLCC) tanker Amjad and crude tanker Al Marzoqah. Bahri did not respond to a request for comment. The UAE foreign ministry has said there were no casualties and the Fujairah port operations were normal. An investigation had been launched in coordination with international authorities, it said, calling on global powers to prevent any parties trying to harm maritime safety and security. Saudi Arabia's foreign ministry in a separate statement voiced support for the UAE, the Middle East's trade and business hub. Gulf stock markets fell on Monday, with Dubai down 2.6% and the Saudi index down over 2%.

Escalating tensions