Moody’s Investors Service said the Swedish banks had only “modest exposure” to the toxic assets that have brought the global financial system to its knees after the collapse of the US subprime or higher-risk home loan market.

Instead, “the significant threat to the sector derives in particular from the sizeable exposure of some Swedish banks to the Baltic countries, which are undergoing a painful and severe economic adjustment,” it said.

“Despite the heightened vulnerabilities, Moody’s still considers the Swedish financial sector to be solid overall, thanks to its robust and stable domestic retail franchises and historically good financial fundamentals, which should represent a good buffer to absorb some deterioration in the key financial ratios,” it added.

The Dagens Industri daily reported on Thursday that the major Swedish banks might have to write off some 170 billion kronor ($18.4 billion) in bad assets over the next three years.

Top bank Nordea has 176 billion kronor invested in eastern Europe, it said, while SEB has 200 billion kronor and Swedbank, the most exposed, has 251 billion kronor.

A fourth lender, Handlesbanken, had little exposure in the region but did have 65 billion kronor in risk assets in Britain, also struggling through recession.

On the Stockholm bourse, the banks were all once again suffering badly in a weaker overall bourse. SEB was down 6.8 percent, Swedbank fell 7.9 percent, Nordea slipped 1.9 percent and Handelsbanken shed 6.9 percent.