The US Department of Defence said its forces boarded an oil tanker linked to Iran, citing sanctions for smuggling Iranian crude oil in Asia.
The M/T Tifani, a Botswana-flagged vessel, was boarded 'without incident' in the Indian Ocean, between Sri Lanka and Indonesia, the Pentagon said.
The move comes amid a US blockade of Iranian ports, extended to all Iranian-flagged ships and those providing material support to the country.
The US aims to disrupt illicit networks and interdict sanctioned vessels providing material support to Iran, anywhere they operate, the Pentagon announcement said.