US Navy forces fire flares at Iranian vessels in the Gulf, amid rising tensions

Iran and the United States traded blame on Saturday after accusing each other's naval forces of provocative actions which culminated in a US helicopter firing warning flares at Iranian vessels.

The US navy said on Saturday that it had reacted to unresponsive vessels belonging to the Revolutionary Guards closing in at high speed on American ships.

"US naval forces attempted to establish communications, with no response from the Iranian vessels. Shortly thereafter, at a safe distance, the US helicopter deployed flares, after which the Iranian vessels halted their approach."

Iran described the move as unprovoked.

"At 4 pm (1130 GMT) on Friday, the supercarrier USS Nimitz and its accompanying warship, while being monitored by the Guards' frigates, flew a helicopter near the Resalat oil and gas platform and approached the force's ships," the Guards said.

"The Americans in a provocative and unprofessional move, sent a warning message to the frigates and fired flares."

Last week, a US Navy patrol ship fired warning shots at an Iranian Revolutionary Guard Corps boat in the Persian Gulf as it closed in on the American vessel, with Iran accusing the US of "provocation and intimidation".

Earlier this year in January, a US Navy destroyer fired multiple warning shots at Iranian patrol boats as they sped toward the ship in the Strait of Hormuz, which connects it to the Indian Ocean.

Last year, Iran briefly captured the crew of two small US patrol boats that strayed into Iranian waters. The 10 US sailors were released 24 hours later.

Tensions have mounted between Washington and Tehran since US President Donald Trump took office six months ago.

The United States on Friday imposed new sanctions targeting Iran's ballistic missile programme, with Iran condemning the measures as "hostile" actions designed to weaken the historic nuclear deal