Stripe, one of the hottest payments startups, has announced it is expanding to Sweden, Denmark, Norway and Finland — a move that puts it in direct competition with Sweden's billion-dollar FinTech startup Klarna.

Speaking at MoneyConf in Belfast on June 15, Stripe's co-founder John Collison, told the Independent.ie:

"We're really excited about expanding more into Europe. We really believe that we're just at the beginning. The barriers for businesses from payments are coming right down and we want to see more of it."

Launched in 2011, the San Francisco-based startup triggered its global expansion plans in late-2012, first launching in Canada. In March 2013, it started expanding to Europe and opened a local office in London. As of the today, the service is available in 20 countries, with more expected this year, Collison told the news outlet.

Stripe has signed up major tech companies, including Apple, Twitter and Pinterest. It made headlines in February when it opened up bitcoin payments for all of its users, after more than a year of beta testing.

The startup, which is rumored to be currently valued US$5 billion, is backed by some of the largest technology venture capital firms, including Sequoia Capital, Andreessen Horowitz, Founders Fund and Khosla Ventures, and is reportedly in the process of raising more capital.

Klarna, on the other hand, provides retailers with a one-click payment feature, and similarly to Stripe, handles payments on their behalf.

According to Business Insider, the company processed US$9 billion worth of transactions globally last year, and handles 30% of all online purchases in Sweden.

The billion-dollar startup, which launched in 2005, is said to be one of Europe's fastest growing companies and currently serves 35 million consumers while working with 50,000 merchants.

In March 2014, Klarna made a bold move when it acquired German competitor SOFORT. The acquisition led the two entities to form Klarna Group, a firm that claims to be the leading European payment provider.

While Stripe is looking at the European market, Klarna is moving forward in its plans to expand to North America.

On Monday, Klarna announced it has hired Michael Rouse, a former American Express executive, as chief commercial officer, who "will oversee new business development, revenue management and global partnerships and solutions."

"The hiring of Rouse is a reflection of Klarna’s global ambition and dedication to consumer loyalty as it prepares to enter the U.S. market," the company said in a release.