Katy Austin
Transport correspondent

An airport source says Nats are now releasing small numbers of aircraft as “trials” at various airports, with a view to ramping up to more regular flights.

Charlotte Simpson
Reporting from Gatwick Airport

I'm at Gatwick and was due to be on the 17:15 flight to Bari, Italy, as I'm due to get married In Puglia on Saturday.

I’ve got my wedding dress with me, I’ve got my fiance with me, but sadly we are not going to be going anywhere tonight.

Our flight is among those that have been cancelled this afternoon because of this disruption with air traffic control.

It's pretty chaotic at the moment, people have just been wondering around looking for help - but from what we've seen they've just had to wait around to be told over the public address system - like us - that their flight is cancelled.

Everyone has been rushing on the phone, trying to call various airlines to try and get re-booked.

Luckily our wedding isn't until Saturday, so we do have a bit of time.

But it isn't the tranquil start to our wedding celebrations that we had imagined unfortunately.

Manish Pandey
Reporting from Malta International Airport

I’m at Malta International Airport, where my flight home to London Gatwick has been cancelled.

The departures board initially showed “delayed” to all UK-bound flights when we arrived, before changing the 21:30 BA flight to cancelled.

The official at the British Airways counter has told us all flights to the UK have been cancelled because of the air traffic issues.

There are a significant number of travellers heading home to the UK.

We’ve been told that accommodation is being worked on, and we will be told through the BA app what the next steps are.

There is frustration from lots of passengers, and the coffee shop in the airport is filling up quickly with exhausted travellers.

For now, the wait continues.

Image source, PA Media

British Airways says it has been informed by the air traffic controller that the "fault has been resolved" but due to the severity of the issue, there will be a "significant knock-on impact for customers and colleagues".

A spokesperson for the airline says it was forced to cancel or divert more than 100 flights this afternoon, "inconveniencing tens of thousands of customers".

This incident was "entirely out of our control and incredibly frustrating for our customers and colleagues," it says, with aircraft and crews ending up out of place.

"We ask customers whose flights have been cancelled not to travel to the airport and to bear with us if they’re trying to get in touch, as our call centres are incredibly busy at the moment.

"Customers due to travel today or tomorrow are able to make changes to their booking on ba.com," it adds.

Theo Whyte
Reporting from Gatwick Airport

There is a long queue snaking back from the service desk at Gatwick airport.

People are frantically checking departure screens and their phones for updates. Others are calling airlines in an attempt to find alternate arrangements.

At the airline check-in desks, passengers are queuing up in front of empty Iberia desks, hoping someone will appear and give them some information.

Shadow transport minister has criticised the government and Nats for allowing another air traffic control incident after a major outage brought UK airports to a standstill last year.

“Yet again passengers are stuck on the tarmac wondering why Britain cannot keep its own skies open," Greg Smith says.

He adds that Transport Secretary Heidi Alexander "promised after last year’s Swanwick fault that she would work with Nats to prevent this happening again. It has happened again.

“The Government and Nats must explain what has happened and how they will make sure resilience is improved.”

Earlier, Alexander said she was "aware" of the technical issue and apologised for the frustration.

Katy Austin
Transport correspondent

What’s really noticeable here at Heathrow Airport is that the skies have fallen quiet.

My understanding is Heathrow reached the point this afternoon where it couldn’t take in any more arriving flights because things hadn’t been departing - and basically the airport ran out of space.

Alfie Tobutt
BBC Your Voice

The queue for Ryanair’s ticket desk here at Dublin Airport stretches almost the entire length of the Terminal 1 departures hall.

There are so many frustrated passengers in the queue that they are blocking the doors at the entrance to the terminal.

While the air traffic control group Nats says it has implemented a fix and systems are “starting to recover”, it will be a while before the situation returns to normal.

Katy Scott
BBC Scotland news

Flights at Scottish airports have also been disrupted by the technical issue at Nats air traffic control.

Glasgow and Aberdeen say some services may experience delays and it is advising passengers to check with their airlines before travelling.

Edinburgh says Nats has implemented a fix, but knock-on disruption is likely throughout the day as operations recover.

Airports in Inverness and the Highlands and Islands say London flights are experiencing “significant delays”, but passengers should check-in at their normal time and check for updates.

Glasgow International Airport has seen 18 flights cancelled today, while 29 have been cancelled at Edinburgh Airport.

Disruption likely to persist for hours to come due to flight backlogpublished at 17:32 BST 8 September

17:32 BST 8 September

Theo Leggett
International business correspondent

Nats says the problem with its flight processing system - which provides air traffic controllers with essential information about aircraft flying through UK airspace - is being resolved.

But the disruption is likely to persist for hours to come.

Here’s the problem. Hundreds of flights have been cancelled and many more delayed across the country.

Although the technical issue affected departures, arrivals were also hit as space on the ground became increasingly restricted. So planes from overseas airports were held on the tarmac as well.

The result is that now there’s a backlog of flights, and aircraft across Europe are in the wrong place. Sorting all of this out is likely to take time.

Rozina Sini
BBC Your Voice

Image source, Chloe Davis

Chloe Davis, 18, from Cambridgeshire, is sitting on a Virgin Atlantic plane at Heathrow waiting to fly to Orlando.

She is an aspiring pilot and is not overly worried about the delays, but would like to know more about what's going on.

"We are stuck in limbo not being able to know because the pilots don't even know what's going on," she tells me.

"I went into the cockpit to speak to the pilots as I myself am an aspiring pilot," she says, adding that Flightradar is the "quietest I've seen airspace in ages".

"It's out of our control, so why worry is my motto," she adds.

Harry Whitehead
Journalist at BBC Guernsey

Guernsey and Jersey airports are facing significant delays and cancellations due to the technical issues with the UK air traffic control group Nats.

Guernsey Airport says it is working closely with airlines and provisions have been put in place to keep the airport open late "if required".

The disruption has meant that Jersey's national football club Jersey Bulls, has had to postpone its FA Cup replay match against Burgess Hill Town FC.

Image source, Reuters

London Heathrow says the issue is affecting arriving and departing flights across UK airports as it apologised to those who are impacted.

The airport is advising passengers to check with their airline for the latest flight information and only travel to the airport if their flight is confirmed.

London Gatwick has asked passengers to check with airlines for information on their flights adding that the issue is affecting them.

London Stansted has similarly asked passengers to check with their airlines before travelling. It says it will continue to monitor the situation and provide updates as more information becomes available.

London Luton, London Southend airport and London City airport have all posted similar statements.

James Kelly
BBC News

Nisha Lahiri, 46, has been sitting on board BA flight BA119 from Heathrow to Bengaluru, India, which has been stuck on the tarmac for more than two-and-a-half hours.

The flight should have departed at 2pm but has been caught up in the disruption caused by an issue with air traffic control.

"We boarded and have been waiting on the aircraft since then. I’m going for a family wedding in two days," she says.

Nisha says passengers are now being offered food, but there won't be any more until two hours before landing after the 10.5-hour flight.

She says the flight is a "priority to depart apparently," adding: "We just don’t know when as the issue with ATC isn’t resolved yet."

"The cabin crew has been helpful, they’re letting passengers use their phones to contact family if needed. Wi-Fi is also free on board."

Image source, BBC Your Voice

Air traffic control group Nats has issued a new statement saying they have issued a fix - with the flight system "starting to recover".

"We are continuing to work closely with our airline and airport customers on recovery," it adds.

Liverpool John Lennon Airport says it is aware of the technical issue with Nats’ air traffic control service, which may have some impact on departures from Liverpool.

Birmingham Airport says the issue is “impacting a significant number of departing flights across the country”. It has advised passengers to arrive in line with their airline's check-in requirements, and to contact their airline directly for the latest flight information and updates.

Manchester Airport Group says it is aware of the issues and it has advised passengers to check their flight status with their airline.

Bristol Airport says technical issues might impact departing flights, but arriving flights are not currently affected. It has told customers to check with their airline for more information.

East Midlands Airport says flights have been affected by the issue, and it has advised passengers to check with their airline providers.

Southampton Airport, Glasgow Airport and Belfast Airport have also issued similar statements on the disruption.

The airline says more than 50 of its flights have been cancelled, while over 65,000 passengers have been delayed by up to eight hours due to the Nats technical issue.

Ryanair criticises Nats for "yet another" system failure causing "widespread delays and cancellations across UK airspace", as it called for the CEO of Nats to quit.

It adds that despite "multiple investigations, reviews, promises and assurances that lessons had been learned, Nats' failures continue".

Nats says it has "identified" the issue and its "engineers are on site and working urgently to resume normal operations as quickly as possible", adding: "We recognise the ongoing disruption to travel, for which we sincerely apologise".

Rozina Sini
BBC Your Voice

Image source, Phil White

Phil White, from Bexhill, hoped to be in Lanzarote after boarding the 13:50 BST easyJet flight from London Gatwick, one of the airports experiencing disruption.

But he has been sitting on the plane for hours, with the plane unable to take off.

"We got on the plane in good time and we are still sitting on the tarmac," he tells the BBC, adding that it is "grim".

"We've been told the radar is down and we can't take off," he says.

"It's comfortable enough but the pilots have been on every 20 minutes saying they are waiting for information from air traffic control and when he finds anything out he will let us know."

• EasyJet has said some of its flights are "unable to operate" as a technical issue is affecting air traffic controller Nats

About 200 flights have been cancelled this afternoon due to the UK air traffic control issue, and that number is expected to rise, according to flight monitoring site Flightradar24.

Air traffic controller Nats says the issue with its “flight processing system” is causing flight disruption across UK airports, adding that “recovery will take some time”.

Theo Leggett
Business correspondent

Departures from a number of airports in southern England, including Heathrow and Gatwick, have been affected by a technical problem affecting the air traffic control provider Nats.

At Heathrow, departures were initially paused around lunchtime. Traffic then resumed, before facing further stop-start disruption in the afternoon.

Incoming flights have been landing as normal. Gatwick said it was currently being affected by the issue, along with other airports.

In a statement, Nats said it was investigating an issue in its flight processing system, which it said was causing some disruption to flight departures.

Engineers were on site, it said, and it's "working urgently to resume normal operations as quickly as possible".

East Midlands has also been affected by the issue, while Manchester Airport warned that some departing flights could be delayed. Passengers have been advised to contact their airlines to check the status of their flights.