Swedish banks' interest margins have come under pressure from the country's ultra-loose monetary policy. The central bank cut rates to an unprecedented -0.35 percent last year and initiated a bond purchase program to stave off stubbornly low inflation. Frank Vang-Jensen, chief executive of Handelsbanken, told CNBC that the negative rates had had "a negative effect in several of our home markets. But the some of what we are doing is that we are growing."