WH Smith’s like-for-like sales grew 2% in the six months to the end of February, working against a 2% decline over the same period last year.

The best Christmas in over a decade helped with this, as the high street retailer started to turn around years of sales drops. Higher revenues at its rail network and airport outlets also increased profit growth.

Over 750 such outlets now exist, compared with 618 high street stores. Over the half year, WH Smith also opened concessions at Dusseldorf and Alicante airports.

Overall revenues rose by 4% with total travel sales up 11% and sales on the high street down 1%.

CEO Stephen Clarke, who joined in 2013, is said to have fixed up the many years of disappointing sales at WH Smith. In turn he was rewarded with a 55% pay rise last year taking his total package to around £4m, including a £550,000 basic salary, £2.5m in long-term share rewards and £783,000 cash.

"The group has delivered a strong first half with both our travel and high street businesses performing well," said Clarke.

"The travel performance reflects our ongoing investment in the UK business and growing passenger numbers while internationally we have now secured over 200 stores, including our first airport shops in Spain and Germany.

"Stationery sales were particularly strong, driven by investment in new product ranges and both our stationery and books business continue to benefit from strong sales in adult activity books, such as colour therapy, extreme dot-to-dot and querkles," added Clarke.

"In March we announced our new exclusive Book Club for young adults headed by the UK's most popular vlogger and bestselling author, Zoe Sugg. The 'Zoella Book Club' will help us to further strengthen our position in a key part of the market."