Ryanair does not expect strike action from staff this summer but air-traffic control problems are likely to cause significant disruption, the airline's marketing chief said today. 

Europe's largest budget airline suffered a number of strikes by pilots and cabin crew last year, grounding hundreds of flights across Europe, having agreed to recognise unions for the first time in 2017. 

While pilot unions in some countries have suspended talks over pay and conditions in protest at the threat of base closures, Kenny Jacobs told journalists he still expects to reach agreement with all the airline's main unions by the end of March, the end of the company's financial year. 

"We don't see a horizon of unrest," Jacobs said, adding that the industrial relations environment at the airline had improved significantly in recent months. 

"We don't see a risk of strikes in the summer. That doesn't mean there won't be," he added. 

The bigger risk to operations is air-traffic control delays, Jacobs suggested. Such delays last year were the worst in Europe for almost a decade. 

"Is it shaping up to be a better or worse summer than last year? I think worse," he said of delays attributable to industrial action by air-traffic controllers. 

To reassure passengers about punctuality, Ryanair said it would apply discounts of 5% on bookings if less than 90% of flights in the previous month were on time. 

The threshold drops to 85% including delays caused by air-traffic control. 

Ryanair also announced the creation of a frequent-flyer scheme under which the payment of a €199 annual fee will allow customers unlimited free seat allocation, fast-track security access and priority boarding. 

Asked if Ryanair might be interested in buying assets from Thomas Cook's airline business, which may be put up for sale, Jacobs said Ryanair was not interested in any large-scale acquisitions but could vie for airport slots should they become available.