Chief executive Nicolas Petrovic said the train operator saw demand fall away following the attacks in the French capital which saw 130 people killed.

However, he added trading started to pick up in 2016 while forward bookings for the summer were “positive”.

He added 10.4 million passengers used the service in 2015, the same as in 2014, while the strength of sterling also had an impact on revenues. At constant exchange rates revenues were flat but with actual rates revenues fell by 5% from £867 million in 2014 to £821 million in 2015.

Underlying profit also fell to £34 million for the year from £55 million in 2014 thanks to the adverse currency rates and other disruption-related costs.

However, the arrival of eight new e320 trains on the route will boost capacity by 20% from 750 to 900 passengers while also improving the passenger experience with free wifi and an onboard entertainment service.

Petrovic said: “After a challenging end to 2015, trading is picking up and the outlook for the summer is positive.

“With our new state-of-the-art trains and highly competitive fares to a range of destinations, we expect this trend to gather momentum over the coming months.

“The successful introduction of our new fleet marks an important milestone for the business as it transforms the travel experience for our customers. 

“Our e320 trains bring the ultimate in style and comfort alongside the latest in onboard digital connectivity for both business and leisure travellers.”