The US has sanctioned three United Arab Emirates-based ship managers and 11 vessels in a move aimed at Iran’s nuclear programme.

The US State Department said a tanker from each of the three companies had been involved in the trade of Iran oil after November 2021 and blacklisted another eight ships in their fleets.

The vessels include one aframax tanker, nine smaller tankers and a tug.

All of the tankers involved in Iranian trades were over 20 years of age, the oldest 26 years, according to the list of affected vessels.

The measures came after the G7 group of countries warned Iran this month of retaliatory action if it continued to promote its nuclear enrichment programme and closer military ties with Russia.

Iran responded by claiming some countries were resorting to “false claims” to justify continued sanctions.

“We remain committed to never letting Iran obtain a nuclear weapon, and we are prepared to use all elements of national power to ensure that outcome,” said US Secretary of State Antony Blinken in a statement.

“As President Biden and the other leaders of the G7 stated earlier this month, Iran must cease its escalations with regard to its nuclear programme as well as its other destabilising actions.”

The vessels targeted late on Thursday included the 28,400-dwt Astra (built 1998), managed by Sea Route Ship Management based in the emirate of Sharjah. The tanker was involved in the trade of Iranian oil in late 2021, according to the US.

The US blacklisted the company and the ship along with three small tankers in the Sea Route-managed fleet, the 18,700-dwt Baltic Horizon (built 2003), the 9,040-dwt Nile (built 2007) and the 9,915-dwt Yamuna (built 2009).

The 68,467-dwt Berenice Pride (built 2001), managed by Dubai-based Almanac Ship Management, was tied to an Iranian trade in October 2022, the US claimed.

Almanac Ship Management is based in Dubai, a rapidly growing centre for the shipping services industry. Photo: Jonathan Boonzaier

Also blacklisted from the Almanac fleet were the 45,560-dwt Euro Fortune (built 2004), the 24,783-dwt Euro Viking (built 2007) and 9,285-dwt Arabian Energy (built 2008). A tug, the 537-gt Harmony, was also targeted.

The tanker linked to Iranian trades in October 2022 was the 73,000-dwt Parine (built 2003), managed by Al Anchor Ship Management, based in Ajman, UAE. An Al Anchor-managed aframax, the 105,540-dwt Road (built 2002), was also targeted.

Ship managers Almanac and Al Anchor have been emailed for comment. Sea Route could not immediately be reached.

The measures mean any assets tied to the companies in the US should be frozen and US citizens are barred from any dealings with the companies and ships.

The US reimposed sanctions on Iran in 2018 as part of former US President Donald Trump’s policy of bringing maximum pressure against its long-time foe. It followed a lifting of oil sanctions introduced under his predecessor, Barack Obama.

But Iran’s oil exports have continued to rise, with exports hitting a post-sanctions high of 1.7m barrels per day in March, according to Kpler cargo tracking. That compared with little more than 800,000 bpd two years ago.