A strike planned by Heathrow Airport workers on Monday has been called off, as talks continue to stop a further walkout on Tuesday.
Some 2,500 workers had planned to strike on both days in a row over pay.
Britain's busiest airport cancelled 177 flights - roughly one in seven departures - after the Unite union rejected a pay offer.
But British Airways said it will now reinstate flights from Heathrow on Monday.
Air Canada said it is planning to operate its full flight schedule on Monday. Aer Lingus confirmed that it will reinstate flights, as will Etihad Airways.
The company added: "Industrial action planned for Tuesday 6 August is still in force but Etihad is committed to operating all services until a final decision is made by unions."
Virgin Atlantic has not cancelled flights, but will continue with its plan to move them from Heathrow to Gatwick.
A spokeswoman for Virgin Atlantic said: "These services will not revert back to the original London Heathrow schedule and will remain in place."
What should passengers do?
A Heathrow spokesman advised passengers to check with their airlines to see if there were any changes to cancelled fights.
He said: "We regret that passengers have been inconvenienced by this and urge them to contact their airline for up to date information on the status of their service."
After being informed by Heathrow that the strike had been suspended, TAP Air Portugal said on its website that it "expects normal operations and the restrictions previously communicated are no longer applicable".
Flybe said its flights on Monday had resumed as normal, although Lufthansa said three flights had been cancelled, with the 365 passengers being booked on to alternative flights.
Swiss and Qatar Airways and were among those to have confirmed cancellations, but it is not yet known if they will now reinstate flights.
Before the suspension of Monday's strike action, airlines had begun to contact affected passengers, after some complained they had been left in the dark about whether their flights were affected.
Heathrow warned that security queues at the airport would be longer than normal, with passengers advised to arrive at least three hours before long-haul departures and two hours before short-haul.
Airlines also said they would impose restrictions on hand luggage to speed up boarding.
Paul Icklow from London, who is meant to fly to Spain with his family on Tuesday, told the BBC earlier that British Airways had been unable to give any information on Sunday morning, leaving him "frustrated".
Meanwhile, Sarah McFadyen from Eastbourne said her flight to Abu Dhabi had initially been cancelled, then Etihad told her it "might still go".
"So I have to turn up at Heathrow four hours before my flight to find out if it's going... I am confused, frustrated."
Heathrow says passengers will be able to rebook their flights for a different day, although choices may be limited given that August is peak holiday season.
How did we get here?
Around 4,000 Unite members voted on the airport's revised pay deal on Friday, with 88% opting to strike.
Heathrow said the offer was worth 7.3% over two-and-a-half years.
Unite regional co-ordinating officer Wayne King said: "This latest vote for strike action points to growing anger among the airport's workers in a whole range of vital jobs which are essential to the smooth and safe running of Heathrow.
"Airport bosses need to heed this latest strike vote and the overwhelming rejection by our members of the revised pay offer which offers little over and above the original offer of £3.75 extra a day for many workers."
Meanwhile, talks aimed at averting a separate strike by British Airways pilots are to continue next week.
Leaders of the British Airline Pilots Association (Balpa) met the company last week to try to resolve the dispute over pay.
The union would have to give two weeks' notice of any industrial action.
Can I claim compensation if my flight has been cancelled?
If your flight out of Heathrow has been cancelled, you should contact your airline to see what you are entitled to in terms of a refund or compensation.
However, if your flight has been cancelled due to airport (rather than airline) staff striking, it is unlikely you will get compensation as this would be considered "extraordinary circumstances" outside of the airline's control, the Civil Aviation Authority said.
In these circumstances, the airport would not have to pay compensation directly to passengers, and whether the airport gives its customers (the airlines) compensation is a commercial issue between the two parties.
If your flight has been cancelled because airline staff are striking, then this would be considered within the airline's control, and therefore you have a legal right to either:
- A full refund, including for flights in the same journey that might be from a different airline (for example, an onward or return flight)
- A replacement flight to get to your destination
- Or - if you are part way through your journey and don't want a replacement flight - a flight back to the airport you originally departed from.
If the cancellation delays you by two hours or more, you are also legally entitled to compensation and help with any costs you may incur as a result of the delay.
Are you due to fly on Monday or Tuesday? Has your flight been affected? Get in touch by emailing email@example.com
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