Kiwi.com has issued a firm rebuttal to Ryanair over accusations the online travel agent released “fake” boarding passes for the low-cost carrier.

Under European Union regulations, it is mandatory passengers complete the official check-in process directly with an airline to ensure they are informed of all safety and regulatory protocols required when travelling.

The Irish airline argues Kiwi.com circumvent these regulations by issuing their own boarding cards - which are not valid on Ryanair flights.

Ryanair director of marketing, Dara Brady, said: “We became aware of these fake boarding passes when a small number of passengers who booked their flights through Kiwi.com arrived at the boarding gate without official Ryanair boarding passes last week.”

He added: “Any passenger presenting a Kiwi.com boarding pass will be refused boarding on Ryanair flights.

“If you made a booking through Kiwi.com we urge you to contact Kiwi.com to obtain the necessary Ryanair booking reference and email address so that you can complete check-in in line with our safety and security protocol.”

Ryanair urged customers to only book direct on the website or app and avoid booking via third party agents.

However, a spokesperson from Kiwi.com denied the accusation.

A statement said: “There is no such ‘fake’ boarding pass - Kiwi.com complies with all the requirements to ensure safe travel for our customers and have done so for years. 

“As well as providing customers with the Ryanair boarding pass, we have also placed it on a Kiwi.com branded background - all the information is the same, just the colours are different.

“Threatening not to board customers is petty and an evil Ryanair practice to try and stifle customer choice.”

The statement added: “The real reason for this action is because Kiwi.com often sells Ryanair tickets cheaper than Ryanair and they don’t like it. 

“Ryanair’s behaviour is nothing short of cruel by putting profit ahead of consumer choice. 

“We will do everything in our power to support our customers through this despicable behaviour from Ryanair who are punishing travellers just because they don’t like competition.”

Kiwi.com is a Czech online travel agency founded by Oliver Dlouhý and Jozef Képesi in 2012.