Terror attack fears mean hundreds of flights will be grounded during the Olympic opening ceremony in Paris in July.

An exclusion zone covering nearly 30,000 square miles means many easyJet, British Airways and Vueling flights from Gatwick are affected.

Three major international airports are also blocked from any plane movements without permission from officials.

The Argus: Passengers have been told to plan aheadPassengers have been told to plan ahead (Image: Getty Images)

Passengers flying away from the UK on their summer holidays may be in for a longer journey  or no trip at all as northern French airspace closes to all flights on Friday, July 26.

The French aviation authority, the DGAC, has ordered the closure during the Olympic opening ceremony for more than five hours to prevent a terrorist attack during the event.

This means flights heading towards southern Europe and Africa from Gatwick will have to take a longer route and passengers heading to France may find their flights cancelled.

The Argus: Charles De Gaulle airportCharles De Gaulle airport (Image: Wikimedia Commons)

Paris airports Charles De Gaulle, Orly and Beauvais airports are affected, meaning hundreds of thousands of passengers from across the globe will be struck by the closure.

The no-fly zone, known as the ZIT, or Zone d'Interdiction Temporaire Ceremonie, is centred on the Notre Dame Cathedral.

A message to pilots reads: "A temporary prohibited area is created to ensure the implementation of the special air security arrangements as part of the protection of the opening ceremony of the Paris Olympic Games 2024.“

The Argus: The scale of the airspace closureThe scale of the airspace closure (Image: DGAC)

Almost 100 easyJet flights heading into Paris have been cancelled as a result of the restrictions including some from Gatwick.

A spokeswoman for the airline said: “Like all airlines operating to and from Paris, easyJet has been requested to reduce its flying programme for duration of the 2024 Olympics opening ceremony on Friday, July 26.

Read more: EasyJet plane U-turns after problem 30,000ft high

“This resulted in the cancellation of 96 flights at both Paris Charles de Gaulle and Paris Orly.

“Impacted passengers were informed in January and provided with alternative travel options.”

The Argus: Paris is gearing up for the OlympicsParis is gearing up for the Olympics

The Olympic Games start in Paris on July 26 and finish on August 11.

A spokesman for Vueling said: "We have been made aware of the potential airspace restrictions over northern France on July 26 due to the Olympic Games opening ceremony but cannot yet specify whether our operations in the UK will be impacted on that day."

British Airways also regularly flies from Gatwick to Paris.