Tui and easyJet have apologised after dozens of flights were delayed or cancelled over the weekend, with further disruption expected over the coming days and weeks.
EasyJet will pre-emptively cancel "around 24" Gatwick flights a day until 6 June, claiming it was necessary "to provide reliable services" over what is expected to be a busy extended bank holiday period owing to the Queen’s platinum jubilee.
It comes after the airline was forced to cancel hundreds of flights last week due to an IT issue.
Tui, meanwhile, said a "combination of factors was causing significant operational disruptions", forcing it to cancel some flights and packages.
The effects were felt at many Tui departure points across the UK and Ireland, including Birmingham, Bristol, Cardiff, Cork, Dublin, Gatwick, Glasgow, Manchester and Stansted.
An easyJet spokesperson said: “We have taken the decision to make advance cancellations of around 24 Gatwick flights per day starting from tomorrow 28 May until 6 June.
“We are very sorry for the late notice of some of these cancellations and inconvenience caused for customers booked on these flights, however we believe this is necessary to provide reliable services over this busy period.
“Customers are being informed from today (Friday) and provided with the option to rebook their flight or receive a refund and can apply for compensation in line with regulations.”
They added easyJet expected to operate around 1,700 flights a day "over the next week", around a quarter of which will operate to or from Gatwick.
In a series of statements, Tui said: "We would like to apologise to some of our customers who have experienced flight delays in recent days. We are doing everything we can to limit any flight delays, which can happen from time to time for various operational reasons.
"Recently, due to a combination of factors causing significant operations disruptions, we made the difficult decision to cancel some of our flights. If you are affected by a flight cancellation and were travelling on a Tui package holiday, this means your whole holiday is impacted and thus cancelled.
"Please accept our sincere apologies for the inconvenience and the disappointment that this decision has caused. Please be assured that we have not taken this decision lightly."
Tui said cancellations were "exceptionally rare" and that by way of apology to those affected, it was offering a £200 holiday voucher per person. Vouchers will be provided within 28 days, while Tui is promising full refunds within 14 days.
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