(Bloomberg) -- President Hassan Rouhani vowed Monday that Iran would respond to an attack on one of its oil tankers in the Red Sea, saying the evidence suggested it was the work of a government not a terrorist group.

Addressing reporters in his first news conference since the U.S. abandoned the 2015 nuclear deal last year, Rouhani said officials in Tehran had seen footage of the incident and it was likely that several rockets were aimed at the tanker. He stopped short of assigning blame, but the vessel was sailing near the Saudi port of Jeddah at the time of the attack.

“This wasn’t a terrorist move, nor was it carried out by an individual. It was carried out by a government,” Rouhani said, adding that officials were also assessing rocket fragments.

Iranian Oil Tanker Attacked as Middle East Tensions Remain High

The Gulf has seen a surge in tit-for-tat attacks on oil facilities, drones and shipping traffic since Donald Trump’s administration tightened sanctions on Iran’s oil exports earlier this year. The measures are part of Trump’s “maximum pressure” policy aimed at forcing Iran to curb its ballistic missile program and support for proxy militia around the Middle East, but have been met with defiance by the Iranian government, which has, instead, rolled back its own compliance with the nuclear accord.

Although all sides have said they want to avoid war, repeated incidents pose a growing risk to supplies from the world’s most important oil-producing region.

The attack on the Sabiti tanker came weeks after a drone strike on a major Saudi oil facility which the kingdom blamed on Iran. Iranian officials have said they weren’t involved in the attack, which rattled global oil markets, and was claimed by Iranian-backed Houthi rebels in Yemen.

--With assistance from Yasna Haghdoost.

To contact the reporters on this story: Golnar Motevalli in London at gmotevalli@bloomberg.net;Arsalan Shahla in Tehran at ashahla@bloomberg.net

To contact the editor responsible for this story: Lin Noueihed at lnoueihed@bloomberg.net

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