Swedish financial technology start-up Klarna has reported an annual loss for the first time, following years of profitability.

Klarna, which lets people buy items online and pay for them over instalments, reported a loss of 1.1 billion Swedish krona ($113 million) on revenues of 7.2 billion krona from January to December 2019.

That puts its accounts in the red for the first time since it was founded in 2005. Klarna had enjoyed the unusual status of being a profitable fintech for years thanks to deals with big-name retailers. Last year, it reported 2018 profits of 161 million krona, which was down from 346 million krona the previous year.

Overall the business is "very healthy" and is seeing "strong growth" in transaction volumes, revenues and merchant growth, a Klarna spokesperson said. The company reported a 31% rise in revenues in 2019, while it also added 75,000 new merchants to its platform.