Iran's judiciary has defended the detention of American oil tankers in Iranian waters as a legitimate act backed by domestic law and the 1982 United Nations Convention on the Law of the Sea, its press service said on May 14.

Asghar Jahangir, spokesman for Iran's judiciary, said the seizures had been carried out on the basis of binding rulings by competent Iranian courts following due legal process, with supporting documentation transmitted to the US side.

"The seizure of offending American tankers is an act grounded in domestic and international law," Jahangir said in a written statement. "The detention of these tankers is based on definitive and final rulings issued by competent Iranian courts after legal procedures have been completed."

Jahangir invoked the UN Convention on the Law of the Sea, arguing that coastal states have the right to detain foreign-flagged vessels for breaches of domestic and international rules within their maritime zones or on the high seas.

The judiciary spokesman drew a contrast between Iranian court-ordered seizures and what he described as US naval conduct in the Gulf. "The legal actions of Iran in seizing offending American tankers are not equal or comparable to the hostile and predatory behaviour of America in maritime piracy against our country's ships. The US president has openly confessed to maritime piracy and even taken pride in it," Jahangir said.

He said Iran's armed forces were continuing to confront US naval assets across the Persian Gulf, while accusing Washington of imposing what he called a maritime blockade in violation of the UN Charter, international humanitarian law and international criminal law.

Jahangir called on the international community and UN-affiliated bodies to push back against what he described as American unilateralism. "The continued silence of the United Nations in the face of American rebellion empties the organisation of meaning," he said.

The statement comes amid heightened tension in Gulf waters following the conflict between Iran, Israel and the United States, with several commercial vessels boarded or detained in recent weeks.

On May 14, the UKMTO maritime reporting agency said a vessel anchored 38 nautical miles northeast of Fujairah had been boarded by unauthorised personnel and was sailing towards Iranian territorial waters, in an incident yet to be formally linked to either side.