The UK publishing industry broke all previous revenue records in 2017 to see collective sales rise 5% to £5.7bn. This was driven by a growth in export sales, which now account for 60% of publishers' revenues. Exports rose by 8% to £3.4bn, consolidating the UK's position as the biggest exporter of books in the world.

However, the Publishers Association has warned that Brexit could damage sales, and that any tariffs or other barriers to trade post-Brexit "could be a problem".  

Last year 36% of its exports were shipped to the European Union, making it the largest market for UK books.

Publishers Association chief executive Stephen Lotinga, said: "It's not just tariffs that could be a problem [post-Brexit]. It's the non-tariff barriers, customs checks and delays.

"That means having books sat in a customs warehouse in Calais rather than in a bookshop in Duesseldorf."

The figures contained in the Publishers Association's latest yearbook show that sales of physical and digital books rose by 4% last year to £3.7bn. Of that exports accounted for £1.6bn, a rise of 7% on the previous year. 

In some sectors exports are even more crucial. Total income from academic journals totalled £1.6bn last year, with £1.4bn of that coming from exports.