The U.S. Treasury Department has put South Korea, China, Japan, Germany and Taiwan on its monitoring list for possible foreign exchange rate manipulation.

Under its Report on Foreign Exchange Policies of Major Trading Partners of the United States issued on Friday, the Treasury said the five countries meet two of the three criteria for "enhanced analysis" but none of them currently meets all three criteria.

The three criteria refer to whether a country has a significant bilateral trade surplus with the U.S. and a current account surplus that exceeds three percent of its gross domestic product, and whether authorities repeatedly intervene in the foreign exchange market to prevent the appreciation of the local currency.

The report said that four of the five countries excluding Taiwan met the first two standards.

The Treasury said in the report that no major trading partner of the U.S. met the standard of manipulating the rate of exchange between its currency and the greenback.

The report said the "Treasury estimates that during the second half of 2015 through March this year, South Korean authorities intervened to resist depreciation of the Korean won during periods of financial market turbulence."

It said this "represented a shift from several years of asymmetric intervention to resist appreciation."