Iran says one of its surveillance planes has shot video and photographed a U.S. aircraft carrier during an Iranian drill near a strategic waterway in the Persian Gulf.

The official IRNA news agency on Thursday quoted Rear Adm. Mahmoud Mousavi as saying this shows Iran's navy is "observing moves by foreign forces" in the area.

IRNA's report didn't provide details or say which U.S.¬ carrier was filmed. It's unclear what value such footage could have.

Iran is holding a 10-day military exercise in international waters beyond the Strait of Hormuz, the passageway for one-sixth of the world's oil supply.

The report follows U.S. warnings over Iranian threats to choke off traffic through the strait if Washington imposes sanctions targeting Iran's crude exports.