London (CNN Business) Starbucks is closing stores and losing money in its most important European market.

partly on costs including store closures and higher wages. The business made a profit the previous year. The coffee chain said Thursday that its UK business lost £17.2 million ($22 million) in the year ended September 2018, a performance it blamedpartlyon costs including store closures and higher wages. The business made a profit the previous year.

While sales increased by about 4%, the company said that was offset by "an increase in our cost of sales, which was driven by our efforts to improve our food menu with higher quality ingredients and more fresh food."

The United Kingdom is Starbucks' sixth-biggest market by number of stores (994 in total), behind the United States, China, Canada, Japan and South Korea.

The American chain is the latest in a series of restaurants and retailers to come under pressure in Britain, where many businesses have struggled with the transition to online shopping and uncertainty about Brexit