SCOTS airport chiefs are calling for greater assurances for passengers over what will happen if Britain crash out of the EU without a deal - as new figures reveal a hit in passenger numbers due to Brexit.

AGS Airports, the owner of Glasgow, Aberdeen and Southampton airports has said it believes that up to ten per cent of flights could be affected if there is a no deal Brexit and has called for less ambiguity over how the country is going to cope on March 29.

It comes as new annual passenger traffic data for 2018 shows that while Europe's airports are flourishing with an average 6.1 per cent annual rise in numbers taking to the air, Britain’s growth has stalled, and were amongst the weakest performers in Europe. Sweden also saw passenger traffic suffer in the wake of the introduction of an aviation tax .

Scotland's three major airports saw an annual rise of just 2.23% with over 27 million taking flights last year.

Airports Council International, which complied the data, said the UK results were "a reflection of mounting Brexit fears on the economy".

HeraldScotland: GV of Glasgow Airport. (34255094)

Glasgow handled 9,662,151 passengers in 2018, a 2.4% drop on 2017 having had the number of routes run by Irish airline Ryanair cut from 23 to three.

Aberdeen was also on the decline dealing with 3,091,087 passengers, an annual drop of 1.4%.

Edinburgh, however, dealt with 14,300,573 passengers, a 6.5 per cent increase in the year, having gained new Ryanair and easyJet routes launched.

With 80,126,856 passengers, London Heathrow, remains Europe's most visited airport, although passenger numbers in the year rose by just 2.7%, while Paris, the second biggest saw a four per cent rise.

Southampton's numbers fell by 3.8%, East Midlands recorded a small drop of 0.1% while London Gatwick, Europe's ninth busiest saw a modest rise of 1.1% along with Manchester (1.6%), Newcastle (1.8%).

Stansted registered the most growth in the year dealing with 27,996,116 passengers in 2018, a 8.1% increase while London City recorded a 6.4% rise.

Some Scottish airports have raised concerns about the uncertainty about air travel when Britain leaves the European Union.

HeraldScotland: Edinburgh Airport

Guidance from the EU indicates that a no-deal Brexit would lead to airlines capping flights at 2018 levels, but tickets are already being sold for 2019 routes.

The International Air Transport Association (Iata) estimates that up to 5 million extra airline seats are at risk of being cancelled if a no-deal Brexit occurs.

And the consumer organisation Which? has raised concerns about a lack of warning for passengers of what will happen if a no-deal Brexit occurs.

It examined the “booking journey” on a number of major UK airlines’ websites last month, and found no warning of the possible impact on travel if a no-deal Brexit occurred.

A spokesman for AGS Airports said: "If we crash out of Europe and lose access to the single aviation market, then, yes, there are real concerns aircraft will be grounded. "In December, the EU came out and said in the event of no deal we would be prepared to allow aircraft to continue to fly to and from the EU for a period of up to 12 months and that provided the industry with a more of a degree of confidence that there will not aircraft grounded and changed how we planned for contingencies.

"However there is this draft regulation that is has been tabled and not adopted that they would cap capacity during that period to levels of 2018.

We still have questions surrounding this draft regulation. There is a lot of ambiguity about it. A lot of things that are not clear about how it would be implemented. We are seeking answers to that.

"It is a waiting game to get clarity to see where this ends up."

"It is thought 90-95 per cent of flights will be unaffected. We would be against any form of cap and we can't say for certain which flights and routes would be impacted.

"As an industry we are calling for certainty and we would want to avoid a no deal."

A spokesman for Edinburgh Airport said: "What we are doing at the minute is keeping talking to Government. It is difficult to say what is going to happen so it is difficult to give any public advice.

"As far as preparing for cancellations and what we think might happen, we don't know. We are always prepared for cancellations. We have processes in place that deal with everything from bomb threats, terrorist threats to weather. We think we have things in place if we have any cancellations."

"In any kind of turbulence, we recommend customers talk to the airlines as they decide whether a plane will fly or not."