SINGAPORE — Singaporeans travelling to the Middle East and Europe over the coming days should be prepared for delays and disruptions, despite a fragile ceasefire between Iran and Israel offering a reprieve to airlines roiled by the fighting in the region.

Late on June 23, operations at two of the world's busiest airports in Doha and Dubai were thrown into chaos as several Middle Eastern countries temporarily closed their airspace, leaving tens of thousands of passengers stranded, including a number of Singaporeans.

But even as airlines resume regular operations, those in the industry said the re-routing of aircraft to avoid the conflict zone will lengthen flight times, especially between Asia and Europe.

"Airlines are already running late for many of the re-routed flights", said Associate Professor Lin Weiqiang, who studies transport issues at the National University of Singapore's geography department.

"We can foresee more flight delays and perhaps schedule changes, if the usual corridors are not reopened soon," he added.

Travel management company FCM Travel Asia has also informed business travellers to anticipate travel delays. Its managing director Bertrand Saillet said this is because carriers are likely to revisit their flight paths and schedules.

Lufthansa Group said none of its flights to Singapore or the Asia-Pacific have been cancelled due to the conflict.

But these flights may take up to an hour longer because of the need to skirt Lebanese, Jordanian, Iraqi, Israeli and Iranian airspace — a key artery for Asia-Europe air traffic before the Iran-Israel conflict erupted.

The airline group said it is also refraining from flying over the northern parts of Saudi Arabia, as well as Bahrain, Qatar and parts of the United Arab Emirates in the Persian Gulf.

Flight tracking data shows that Lufthansa's flights between Singapore and Frankfurt, for instance, have been flying north of Iran, travelling through Pakistan, Afghanistan and Turkmenistan airspace instead.

This is the same "northern" flight path that some carriers like Singapore Airlines (SIA) have been using to fly to and from Europe.

NUS' Prof Lin said he expects airlines to continue re-routing flights via Pakistan, Afghanistan and Turkmenistan over the next few days, and possibly weeks.

This may add to the congestion there. "As it is, Afghan airspace is already capacity controlled and is subject to air traffic flow management since 2007," he noted.

Even before the airspace closures on June 23, which were triggered by Iran's missile strike on a US military base in Doha, SIA and its budget arm Scoot had already cancelled flights to the Middle East.

After a security assessment, SIA cancelled all of its Singapore-Dubai flights from June 22 to June 25. Meanwhile, Scoot cancelled its Singapore-Jeddah services on June 23 and June 26, citing operational considerations.

In contrast, Middle Eastern carriers like Emirates, Etihad and Qatar Airways continued to fly to Singapore during this period.

Asked why this was the case, Prof Lin said the airlines have different operational considerations, and it is likely that SIA Group was unwilling to risk its assets becoming collateral damage or getting stuck in the Middle East.

Qatar Airways said on June 24 that it has deployed additional ground staff at Hamad International Airport, its home base, as well as other key airports to help affected travellers and minimise disruptions.

According to flight tracking website FlightRadar24, around 250 flights were cancelled at Hamad airport, with another 238 delayed, after Qatar, Bahrain and Kuwait temporarily shut their airspace on June 23.

Airports across Dubai in the United Arab Emirates also briefly halted operations.

Dubai-based Emirates said there were some cancellations and a few flights had longer routes due to airspace congestion, but its passengers experienced minimal disruptions as regularly scheduled flights resumed within a few hours.

The carrier confirmed that none of its Singapore-Dubai flights were re-routed.

"The airline would never fly if it was not safe to do so. Emirates continuously monitors developments, coordinates with aviation authorities and assesses every potential risk," it added on June 24.

A day earlier, the airline had said in an update that it will continue to operate flights as scheduled, using flight paths "well distanced" from conflict areas.

Other carriers like Air France have also begun to resume flights to the Middle East.

The French carrier told ST that it plans to resume services from Paris to Dubai and Riyadh starting June 25, and restart flights between Paris and Beirut in Lebanon from June 26.

The airline said it is closely monitoring the situation in the Near and Middle East in real-time. "Air France reiterates that the safety of its customers and crew is its absolute imperative," it added.

For Australian flag carrier Qantas, which had two flights from Perth to Europe diverted as a result of the airspace closures in the Middle East, normal operations have also resumed.

Its Europe-bound flights on June 24 departed Singapore and Perth without a hitch.

Qantas has been re-routing its European flights to avoid conflict zones in the Middle East for weeks now, but some, like the two diverted flights, have been taking a "southern" route over Oman, Saudi Arabia and Egypt.

The airline said on June 24 that it continues to monitor airspace availability closely, and it will alter its schedule as required.

NUS' Prof Lin said he believes it is safe for travellers to fly to where airlines are allowed to operate. What is more likely in the next few days is sudden disruptions and airspace closures, given the volatility of the situation.

"Travellers should strive to leave enough time for connections in case of any delays or misallocation of equipment," he said.

Those who wish to further minimise risks when flying to Europe could also opt for airlines that maintain a wider berth from the conflict area, he added, pointing to Cathay Pacific, which flies to Europe via Xinjiang and Central Asia, as an example.

This article was first published in The Straits Times. Permission required for reproduction.