Iranian authorities refused to fuel the aircraft of Pakistan Prime Minister Nawaz Sharif during his visit to Tehran last month to make the state-run PIA clear its dues amounting to just over USD 5000.

"The Iranian airport authorities had refused to fuel the Pakistan PM's aircraft at the Tehran airport on May 12 and warned it would not release the plane until the PIA cleared the outstanding payment," a senior Pakistan International Airlines official told PTI.

The outstanding amount just over USD 5,000.

"The Iran Air officials responsible for handling the VVIP flight showed their annoyance over the PIA failure in clearing the pending invoice of PK-788 despite the passage of four months," the official said.

The warning alerted the PIA bosses who directed its official in Tehran to clear the amount forthwith and save Pakistan from the embarrassment.

The PIA managed to hide the issue from the foreign office and the prime minister.PIA spokesman Mashhood Tajwar denied the prime minister's aircraft was held at Tehran airport over payment issue.

"We had already made the outstanding payment of USD 5,646," he said.

According to details, the PK-788 (London to Karachi flight) had to make an emergency landing at the Tehran Airport on January 18, 2014 when a passenger, Abdul Jabbar Abbasi, reported some serious health problem and died later.

The Iran Air was requested to make all required arrangements plus ambulance with doctor before the landing of the aircraft.

The passenger was taken to Azadi Hospital after the landing.

The amount of over USD 5000 was to be paid in terms of landing, parking, navigation, weather and fuelling of the aircraft but due to unavailability of cash, the aircraft was cleared on credit by the airport authorities.

The Iran Air paid USD 5646 for these ground handling services.