Iran has detained 13 fisherman from two United Arab Emirates vessels which crossed into what Iran claims as its territorial waters in the Gulf, the Iran-based Press TV has reported.

The 12 Emirati nationals and one Indian national were transferred to a military dock, Press TV quoted base commander Colonel Ali Vesali as saying on Thursday.

"The (Iranian) forces at Abu Musa Marine Patrol Base detected two intruding UAE vessels while fishing in the Persian Gulf waters and issued the order for capturing them," Vesali said.

Political relations are strained between the two oil-rich countries which face each other across the Gulf.

The two countries disagree over who has jurisdiction over three small but strategically important islands near the entrance to the Strait of Hormuz.

The three islands of Abu Musa and Greater and Lesser Tunb have been held by Iran since 1971, shortly before the seven Gulf emirates gained full independence from Britain and formed the UAE, now allied with Washington.

In May, the United Arab Emirates criticised a visit by Iranian politicians to the disputed islands.