Buy now, pay later service Klarna has reached a valuation of $31bn after completing a $1bn equity funding round, making it the highest-valued private fintech in Europe and second highest in the world after Stripe.

The four times oversubscribed funding round comes ahead of the Swedish company’s likely public listing later this year. It included a combination of new and existing investors, though Klarna has not disclosed who they are. Some of Klarna’s current investors include Macy’s, Snoop Dogg, Sequoia Capital, Visa, BlackRock, Ant Group, TCV, and Silver Lake, among others.

Klarna intends to use one per cent of the capital raised for an initiative focusing on key global sustainability challenges. The initiative will launch on April 22’s World Earth Day.

“At Klarna, we solve problems – that is the heart of what we do for both consumers and retailers,” said Sebastian Siemiatkowski, Co-founder and CEO of Klarna. “Consumers want transparent products to help them bank, shop and pay that reflect the way they live their lives, not just outdated traditional models. Each and every one of us at Klarna will continue to work hard on this, but it is also time for us, with our culture of change, disruption and innovation, to focus on tackling bigger, more complex issues. I believe our industry has a responsibility to help in some way solve global sustainability issues and I hope others will join Klarna in our ambition.”