John Bolton, the US national security adviser, blamed Iran for the sabotage of four oil tankers off the United Arab Emirates, warning of a “very strong response from the US” against the Islamic republic and its proxies.
“I think it is clear these [tanker attacks] were naval mines almost certainly from Iran,” Mr Bolton told reporters in Abu Dhabi on Wednesday. “Who else would you think is doing it? Somebody from Nepal?”
Four oil tankers were hit in an attack off the coast of the UAE earlier this month in an incident that Iranian officials have described as suspicious.
“There is no doubt in anybody’s mind in Washington who was responsible for this,” Mr Bolton said. “It is important for the leadership in Iran to know that we know.”
Mr Bolton’s statement threatens to reinflame tensions with Tehran after weeks in which the Trump administration has mixed threats with statements playing down the odds of a US-Iran conflict.
A spokesman for Iran’s foreign ministry said it was a “ridiculous accusation” but “not a strange thing” given Mr Bolton’s long record of hostility towards Iran.
The US national security adviser said American special forces had contributed to the investigation into the incident, which damaged Saudi, Emirati and Norwegian vessels. The UAE has yet to apportion blame for the attacks.
Mr Bolton said they were connected to two other incidents over the past three weeks: a drone strike on a Saudi pipeline claimed by the Iran-allied Yemeni Houthi militia and a rocket fired into a park near the US embassy in Baghdad. A previously unreported, unsuccessful attack on the Saudi port of Yanbu, which took place a few days before the tanker sabotage, may or not be have been linked to the other incidents, he added.
Earlier this month the White House said the US was sending an aircraft carrier strike group and B-52 bombers to the Middle East after intelligence suggested Iran might be preparing to attack American forces. Last week US president Donald Trump said the US would move an additional 1,500 troops to the region.
Mr Bolton said the US deployments were designed to act as a deterrent and had so far been successful.
“The point is to make it clear to Iran and its surrogates that these kind of actions risk a very strong response from the United States,” he said. The US would be “prudent and responsible” in its approach, he added.
Mr Bolton’s remarks went beyond those of Mike Pompeo, US secretary of state, who said last week it was “quite possible” Iran was responsible for the sabotage attacks.
Iran is seeking to resist US pressure without provoking Washington. But there is anger in Tehran at Saudi Arabia and the UAE, which are perceived to be encouraging the Trump administration to punish Iran.
Iran’s President Hassan Rouhani said on Wednesday that doors were not closed to negotiations with the US if it showed “in practice” that it could adhere to “justice and law” in dealing with Iran.
Mr Bolton said the Iranian Revolutionary Guards’ overseas Quds Force, and its leader Qasem Soleimani, were using Shia militia groups in Iraq to indirectly attack US diplomatic facilities in the country.
“We have made it clear that we are going to hold the Quds Force responsible if we see attacks like the one in Baghdad, whether it was intended as a signal we don’t know,” Mr Bolton added.
“But we know who sends these rockets into Iraq, we know who trains the Shia militia groups, we know who finances the Shia militia groups, we know who to a large extent directs their activities,” he added. “We will hold them responsible if they make the mistake of going further.”
The four attacks were consistent with US intelligence that prompted the deployment of more US forces in the region.
Mr Bolton said Iran had no reason to break the limits on enriched uranium and heavy water agreed as part of its nuclear deal with global powers, unless that was part of an effort to reduce breakout time needed to produce nuclear weapons.
“That is a very serious issue if they continue to do that,” he said. He added that it provided graphic evidence that the nuclear deal — which Mr Trump pulled out of last year — had failed to constrain “Iran’s desire for nuclear weapons, their terrorist activities in the region and other malign behaviour.”
Mr Trump, however, was willing to negotiate with Iran, he said: “That is a possibility, but the end result is no deliverable nuclear weapons.”