The ScanEagle is a 4-ft (1.25-metre) long “off the shelf” spy plane manufactured by U.S.-based Boeing. The company also supplies and operates drones for customers in several Middle Eastern countries, including to help ensure oil platform security in the Gulf, according to its website.

Iran and OPEC rival Saudi Arabia have also accused each other of violating each other’s territory near oil and gas fields in the Gulf over the past year.

VIOLATIONS

In November, the United States said Iranian warplanes shot at a U.S. surveillance drone flying in international airspace. Iran said the aircraft had entered its airspace to spy on Iranian oil platforms and said it would respond “decisively” to any incursions.

Days later Iran’s ambassador to the United Nations, Mohammad Khazaee, wrote to Secretary-General Ban Ki-Moon to complain about alleged repeated U.S. violations of Iranian airspace, describing them as “illegal and provocative acts”.

Khazaee said that U.S. craft had entered southern Iran seven times in October around Bushehr where Iran’s only nuclear power station is situated.

A year ago to the day, Iranian forces announced they had captured a U.S. RQ-170 reconnaissance drone in eastern Iran which was reported lost by U.S. forces in neighbouring Afghanistan.

Iranian commanders have since announced they have extracted valuable technology from the aircraft and were in the process of reverse-engineering it for their own defence industry.

The United States and its allies believe Tehran is trying to develop nuclear weapons and have imposed tough economic and financial sanctions. Iran says its programme is purely peaceful.