File photo of travellers stranded
Airlines are continuing to cancel and divert flights serving the Middle East after the US and Israel launched strikes against Iran.
British Airways and Virgin Atlantic are among carriers to have grounded flights, with flights in and out of Dubai International and Al Maktoum International airport in Dubai suspended.
The Foreign Office is warning British citizens against all but essential travel to Bahrain, Kuwait, Qatar and the United Arab Emirates (UAE). Those already there have been advised to shelter.
This came after Iran launched retaliatory attacks on the Gulf states.
Long-haul travel is being affected more widely and Heathrow has urged travellers to check with their airlines.
One person has been killed and 11 others were injured at airports in Dubai and Abu Dhabi. Four of those injuries were among members of staff at Dubai International.
Emirates has suspended all its operations in and out of Dubai until 15:00 local time (13:00 GMT) on Sunday due to airspace closures across the region, while Etihad suspended flights out of Abu Dhabi until 14:00 local time.
British Airways has cancelled services to Tel Aviv and Bahrain until Wednesday.
It said services between Heathrow and Abu Dhabi, Amman, Bahrain, Doha, Dubai or Tel Aviv could be affected for several days.
Sarah Short was due to return from a holiday in Dubai to Heathrow.
"We got on the plane and were literally about to taxi when the pilot said: 'We have some bad news - we're not going anywhere'," she told the BBC. "We then sat on the plane on the tarmac for over three hours."
Airspaces over Iran, Israel, Iraq, Qatar, Bahrain, Kuwait, Syria and the UAE remain closed on Sunday morning, while there is a partial closure in Saudi Arabia. Jordanian and Lebanese airspace remains open but there is limited flight activity.
Virgin Atlantic said it was suspending services between Heathrow and Riyadh on Sunday, after earlier cancelling flights from Heathrow to Dubai on Saturday and Sunday.
It has warned that flights to India, Saudi Arabia and the Maldives may take longer due to them being rerouted around the affected region.
Virgin is among airlines across Europe, Asia and the Middle East that have had to cancel or reroute flights to avoid the closed or restricted airspace.
Tracking shows flights between Europe and Asia travelling via Saudi Arabia or the Caucasus.
Emma Belcher and her husband Vic were on their way back to Heathrow from a holiday in the Maldives via Dubai when their connecting flight was cancelled.
"There is absolutely no information about when they might open airspace so we don't know how long we'll be here," she said.
"We were really looking forward to getting home to see the children as we haven't been away without them before."
Qatar Airways confirmed the temporary suspension of flights in and out of the capital, Doha, due to the closure of Qatari airspace, saying operations would resume at 19:00 local time on Sunday (16:00 GMT).
John Henry, 71, from Northampton, who is on holiday in Qatar, was at a shopping centre when they received an air raid alert on Saturday.
"We heard a bit of a thud and felt a tremor, and we saw a number of people moving quickly out of the shopping centre," he told the BBC.
Qatar's defence ministry said it had intercepted Iranian missiles after explosions were heard in Doha.
As a result of the disruption:
Aegean Airlines, Greece's largest carrier, suspended flights to and from Tel Aviv, Beirut and Erbil until Monday.
Air Astana has cancelled all flights to the Middle East until the end of Tuesday
Air Canada cancelled flights to Dubai until Tuesday, and to Israel until next Sunday.
Spanish carrier Air Europa cancelled services to Tel Aviv until at least Monday
Air India has cancelled flights from Delhi, Mumbai and Amritsar to a number of destinations including London, New York and Paris
Azerbaijan Airlines has suspended flights in and out of Dubai, Doha, Jeddah and Tel Aviv
FlyDubai suspended flights to and from Dubai until 15:00 local time (11:00 GMT) on Sunday
Indian airline Indigo has cancelled dozens of flights until Tuesday due to the airspace restrictions
ITA Airways suspended flights to and from Tel Aviv and said it would avoid Israeli, Lebanese, Jordanian, Iraqi and Iranian airspace until next Saturday
KLM cancelled services to Dubai, Dammam and Riyadh, having already suspended its Amsterdam-Tel Aviv service
LOT suspended flights to Tel Aviv until 15 March, and cancelled flights to Dubai and Riyadh until Monday
Lufthansa has suspended services to and from Tel Aviv, Beirut and Oman until next Saturday, and flights in and out of Dubai on Sunday
Norwegian Air suspended all flights to Dubai until Wednesday
Pegasus Airlines cancelled all services to Iran, Iraq, Jordan and Lebanon on Sunday
Turkish Airlines has cancelled flights to Lebanon, Syria, Iraq, Iran and Jordan on Sunday
Wizz Air has suspended all flights to and from Israel, Dubai, Abu Dhabi and Amman up until and including next Saturday