British Airways expects to maintain 99.5% of all flights during a 16-day cabin crew strike which started on Saturday.
Short-haul aircraft from partner Qatar Airways have been drafted in to cover some services.
However, BA cancelled flights to and from Doha, Muscat as well as to Abuja in Nigeria over the weekend.
The airline said a “very small number”of long-haul services from Heathrow had been merged
“We expect to operate all short-haul flights to and from Heathrow, with our Oneworld alliance partner Qatar Airways flying a small number of these services on our behalf,” BA said.
“We will be updating all of our operational systems with the details of which flights are being served by Qatar on a regular basis.”
All flights to and from Gatwick, London City and Stansted will operate as normal together with recently launched weekend-only Mediterranean services to and from Birmingham, Bristol and Manchester, according to the airline.
Cabin crew union Unite failed in a last ditch bid to prevent BA from wet leasing nine Qatar Airways aircraft to run certain services during the walkout by mixed fleet cabin crew which runs until July 16.
The union had called on the Civil Aviation Authority to block the move, claiming it breached European regulations for airlines wet leasing aircraft form outside the EU.
This is the latest stage in a row over alleged poverty pay for cabin crew which has resulted in 26 days of strike action previously this year.
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