Saudi Crown Prince Mohammed Bin Salman accused Iran of the twin tanker attacks. (File photo)

Saudi Crown Prince Mohammed bin Salman accused arch-rival Iran of attacks on oil tankers in a vital Gulf shipping channel, adding he "won't hesitate" to tackle any threats to the kingdom, according to an interview published on Sunday.

Two tankers were struck by explosions on Thursday in the Gulf of Oman, the second attack in a month in the strategic shipping lane amid a tense US-Iran standoff, sparking fears of a regional conflagration and sending oil prices soaring.

"We do not want a war in the region... But we won't hesitate to deal with any threat to our people, our sovereignty, our territorial integrity and our vital interests," Prince Mohammed told pan-Arab daily Asharq al-Awsat, in his first public comments since the attacks.

"The Iranian regime did not respect the presence of the Japanese prime minister as a guest in Tehran and responded to his (diplomatic) efforts by attacking two tankers, one of which was Japanese."

The prince also accused "Iran and its proxies" over May 12 attacks on four tankers anchored in the Gulf of Oman off the United Arab Emirates port of Fujairah.

Thursday's attack on two tankers -- the Japanese-owned Kokuka Courageous that was carrying highly flammable methanol when it was rocked by explosions and the Norwegian-operated Front Altair -- came around the time Japanese Prime Minister Shinzo Abe was meeting with Iranian leaders in Tehran.

US President Donald Trump has said the twin attacks had Iran "written all over it", rejecting Tehran's vehement denial.

Saudi Arabia, a close US ally, is a bitter regional rival of Iran.

The US military on Friday released grainy footage it said showed an Iranian patrol boat removing an "unexploded limpet mine" from one of the tankers.

The UAE's Foreign Minister Sheikh Abdullah bin Zayed Al Nahyan on Saturday called on world powers "to secure international navigation and access to energy", a plea echoed by regional ally Saudi Arabia after the incident sent crude prices soaring.

Iran has repeatedly warned in the past that it could block the strategic Hormuz Strait in a relatively low-tech, high-impact countermeasure to any attack by the United States.

Doing so would disrupt oil tankers travelling out of the Gulf region to the Indian Ocean and global export routes.

The UAE's Sheikh Abdullah, whose country is bitterly opposed to Iranian influence in the region, called for a deescalation of tensions.

"We remain hopeful in attaining a broader framework for cooperation with Iran," he said at a summit in Bulgaria.

Meanwhile, Saudi Arabia's Energy Minister Khalid al-Falih called for a "swift and decisive" response to threats against energy supplies after Thursday's "terrorist acts".

Vessels Head To Port

The Japanese tanker's Tokyo-based operator Kokuka confirmed Saturday the stricken vessel was heading to port in the UAE.

"We still don't know if the tanker goes to Khor Fakkan or Fujairah as they are very close," said a spokesman, referring to two Emirati ports on the Gulf of Oman.

Maritime experts would then seek to transfer the highly flammable cargo to shore, according to an unnamed official quoted by Japanese state media.

"From a viewpoint of global energy security, it is necessary for the international community to jointly deal with the act," said Japanese trade minister Hiroshige Seko at a G20 energy and environment meeting in Japan on Saturday.

The other ship, the Front Altair, has left Iran's territorial waters, multiple sources said Saturday.

The ship is "heading toward the Fujairah-Khor Fakkan area in the United Arab Emirates", head of ports for Iran's southern province of Hormozgan told the semi-official news agency ISNA.

The tanker "has left Iran's territorial waters," he said, adding that it was being towed and sprayed with water to cool the hull.

A spokeswoman for Frontline Management, the Norwegian company which owns the ship, said "all 23 crew members of the tanker departed Iran" and flew to Dubai on Saturday.

"All crew members are well and have been well looked after while in Iran," she said.

'Allegations Against Iran'

Iranian Foreign Minister Mohammad Javad Zarif tweeted that the US had "immediately jumped to make allegations against Iran without a shred of factual or circumstantial evidence."

The United States has also accused Iran over May 12 sabotage attacks on four tankers anchored in the Gulf of Oman off Fujairah.

British Foreign Secretary Jeremy Hunt said London had concluded Iran was "almost certainly" responsible for Thursday's tanker attacks.

Iran's foreign ministry responded on Saturday by summoning British Ambassador Rob Macaire over Hunt's "false remarks", the official IRNA news agency reported.

UN Secretary-General Antonio Guterres called for an independent investigation.

"It's very important to know the truth (and) that responsibilities are clarified," he told reporters at UN headquarters in New York.