TEHRAN: Iran is investigating a claim of a near-miss in its airspace between two Pakistani passenger jets due to human error by air traffic controllers, state media said on Wednesday.

The report comes a day after Pakistan International Airlines said two of its planes flying at high altitude over Iran came within 1,000 feet (300 metres) of each other on Sunday.

The Pakistani flag carrier said Iranian air traffic controllers had cleared Peshawar-bound PIA flight PK-268 to descend to 20,000 feet from 36,000, leading to the close call with PIA flight PK-211 which was at 35,000 feet and en route to Dubai.

The Civil Aviation Organization of Islamic Republic of Iran said an investigation had been launched into the near-miss.

“Appropriate measures have been taken to obtain documents of the country’s control centre, and we requested reports from the pilots of the planes for further investigation,” said CAO deputy head Hassan Khoshkhoo.

“Normally, after receiving all the documents, the issue is reviewed … and the final result is announced,” he told state broadcaster IRIB.

PIA spokesman Abdullah Hafeez Khan told AFP a cockpit “collision avoidance system helped the two pilots to correct the course and avoid a collision after the planes came close to each other”.

Khoshkhoo said the planes had been equipped with the system that “gives the necessary warnings from a long distance,” adding that “such incidents have also happened in other countries”.

“We will write to the Iranian authorities to investigate the incident as the ATC (air traffic control) should not have cleared the Peshawar-bound flight to descend,” he added.

Sanctions-hit Iran has suffered several air disasters in recent years, with officials complaining of difficulties in acquiring spare parts to keep its ageing fleets in the air.