A top Omani diplomat was in Iran on Saturday for bilateral talks after weeks of volatility over the Strait of Hormuz, the passageway for a fifth of all globally traded crude.
Oman, seen as a neutral Gulf Arab country that has acted as a facilitator of talks between the US and Iran in the past, sits across the strait from Iran, at the mouth of the Persian Gulf.
The Omani diplomat's visit to Tehran comes amid a spike in tensions between Washington and Tehran stemming from President Donald Trump's decision last year to withdraw the US from Iran's nuclear deal with world powers and impose sweeping sanctions on the country.
The meeting between Omani Minister of State for Foreign Affairs Yusuf bin Alawi and Iran's Foreign Minister Mohammad Javad Zarif is seen as a possible effort at diffusing a diplomatic standoff with the UK, after Iran seized a British-flagged tanker in the Strait of Hormuz earlier this month.
However, neither Oman nor Iran has confirmed that mediation efforts are underway.
Iranian officials have said the Stena Impero with its crew of 23 aboard had violated international shipping laws during its transit through the Strait of Hormuz, but other senior Iranian officials have also suggested it was seized in retaliation for the British navy's role in seizing an Iranian supertanker first, off the coast of Gibraltar over violations of EU sanctions on oil sales to Syria.
The Royal Navy helped impound the Iranian ship that was carrying more than 2 million barrels of crude near Gilbratar, a British overseas territory, on July 4.
More From This Section
That ship's crew is being held aboard the vessel, as is the crew of the Stena Impero, which is now near the heavily guarded Iranian port of Bandar Abbas. The crew are mostly Indian, but also include Filipino, Russian and Latvian nationals.
Iran's President Hassan Rouhani suggested this week that Iran might release the British-flagged ship if Britain takes similar steps to release the Iranian oil tanker.
Tensions have flared amid political changes in the UK that saw Boris Johnson become the new prime minister this week. It's unclear how the new government will respond to Rouhani's suggestion or the impasse with Iran.
In past weeks, Iran has shot down a US spy drone and US officials say military cyber forces struck Iranian computer systems that handle missile and rocket launchers.
Also earlier, six oil tankers have been sabotaged near the Strait of Hormuz.