Iranian authorities have introduced an air traffic orientation scheme to ease the passage of Qatari flights to Europe and Asia following the airspace ban imposed by several Arab states.
The measures are designed to allow northbound aircraft departing Qatar to access Turkish airspace through western Iranian airways, while southbound aircraft can travel to Oman and Karachi airspace via routes in the vicinity of Iranian islands.
Qatar Airways has extended its suspension of flights to include services to the United Arab Emirates, Bahrain and Egypt having previously confirmed it was halting operations to Saudi Arabia.
All four countries have introduced restrictions on Qatari operations after a simmering diplomatic row escalated into a crisis. Qatar Airways serves a total of 18 destinations across the four states, according to FlightGlobal's schedules database.
The airline says the suspension will remain "until further notice".
Qatar is fully enclosed within the Bahrain flight information region. NOTAMs for the Bahrain FIR state that all flights registered in Qatar are "not authorised" to overfly Bahraini airspace.
"No flight will be allowed from the kingdom of Bahrain to the state of Qatar and from the state of Qatar to the kingdom of Bahrain," the NOTAMs add.
But affected flights, they state, can exit Doha's Hamad airport by operating along airway UT430 to the RAGAS waypoint and return via UR659 through the MIDSI waypoint. Both waypoints are situated in the Arabian Gulf on the border between Bahraini and Iranian airspace.
Corresponding NOTAMs for Iranian airspace state that, owing to the "regional crises" in Bahrain and Qatar, traffic can access Turkish airspace by operating through the LAGSA waypoint, south of Shiraz, and travelling through western Iran to the Ankara FIR entry points at ALRAM and TESVA.
Southbound traffic can operate along airway M561 via the Iranian islands of Kish and Qeshm to the Muscat and Karachi FIRs.
The Iranian traffic scheme centres on altitudes from 15,000-19,000ft outbound from Qatar and 24,000-26,000ft inbound.
Saudi Arabian, United Arab Emirates and Egyptian NOTAMs specifically state that Qatari-registered aircraft are prohibited from operating to the three countries' airports and banned from overflights.
But they also add that other international flights, which intend to use any of the three countries' FIRs to access Qatar, must obtain prior approval from the respective civil aviation authorities.