Flight disruption could continue into the week amid the ongoing technical fault affecting UK air traffic control.
Earlier, it was reported by Scottish airline Loganair that a "network-wide failure of UK air traffic control systems" had occurred.
Soon after, a number of other airlines reported similar issues, seeing a number of flights grounded and passengers left stranded.
This air traffic control issue, which is likely to cause chaos throughout the day, could see disruption continue into the week, a leading travel journalist has suggested.
Leading Travel journalist suggests flight disruption could continue into the week
Simon Calder told Sky News that "hundreds of thousands" of people will be flying into the UK today, adding that "disruption could last into the week".
He continued: "This is the last thing anybody needs", telling the broadcaster that planes would be touching down in places like Paris and Amsterdam instead of the UK.
"I'm afraid experience tells us something like this is not going to end quickly, it's going to be very messy."
He stressed that passengers would be safe and that contingency plans would be at play.
However, he warned: "If you're booked to fly into or out of the UK be prepared for serious disruption."
Calder said there will be "many thousands of people waking up tomorrow somewhere they don't want to be".
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