The United States is moving to tag Korea as a currency manipulator at a time when the country is struggling with plunging exports, local observers said Wednesday.

Korea and other countries that have consistently posted trade surpluses with Washington will likely be designated currency manipulators in the coming months after U.S. President Barack Obama signs an amendment to a related bill, according to the local observers.

"Korea along with Taiwan may be among the first to be designated as countries that fix exchange rates to bolster exports," said Korea Economic Research Institute (KERI) senior researcher Kim Seong-hoon.

"Such a move can lead to indirect sanctions by the International Monetary Fund (IMF) and World Trade Organization, followed later by local companies being penalized when trying to do business with U.S. partners."

Besides Korea and Taiwan, Washington has cited China and Israel as countries that intervene in the foreign exchange market.

Local experts said the expected move by the United States comes as data showed the Korean won depreciating 10 percent as of last month compared to late 2014.      

They, however, cited data by the Bank for International Settlements (BIS) that shows that if the movement of other currencies are calculated, the value of the won backtracked 1 percent vis-a-vis the greenback.

"Other countries have taken steps to weaken their currencies, and such a trend has resulted in no real advantage for Korea," said Bae Min-keun, an economist at LG Economic Research Institute (LGERI). The Japanese yen and euro, in particular, have depreciated more than the won.

The won's value fell to 1,208.4 won to the dollar as of January from 1,099.2 won at the end of 2014, but the effective exchange rate index released by the BIS showed the currency dipping to 108.22 from 109.23 in the same period.

Reflecting the lack of benefits, Asia's fourth-largest economy said that in the first month of this year exports nosedived 18.8 percent on-year to $36.7 billion last month, the sharpest drop since the 20.9 percent plunge reported for August 2009.

The January figure represents a much steeper fall than the 14.1 percent decrease tallied for December and the 8 percent fall for all of 2015.

The BIS, moreover, said of the 61 countries checked, the real exchange rate of 45 depreciated compared to late 2014.

Local experts, meanwhile, said that the United States does not seem to have clear-cut guidelines on what constitutes currency manipulation.

"The U.S. uses estimates by the IMF and the Peterson Institute for International Economics that have argued the equilibrium rate of exchange should be 800 won to the U.S. dollar," Bae said, hinting that this estimate is not realistic.

Local experts also said that the recent spike in the country's current account surplus, cited for causing the U.S. to think that Seoul was intervening to keep is currency weak, is a temporary development.

Korea's current account surplus of around 6 percent of its GDP is mainly due to a sharp drop in its crude prices, with this number expected to go down once energy prices return to normal. (Yonhap)