The U.S. Treasury said in a semiannual report Friday that no major U.S. trading partner met the qualifications for being labeled a currency manipulator. China remained on the Treasury's "monitoring list" for currency practices and macroeconomic policies, while Russia is not on the list.

"Russia and China are playing the Currency Devaluation game as the U.S. keeps raising interest rates. Not acceptable!" Trump said in a tweet.

China's weakened investment and increasing corporate and local government defaults may be President Xi Jinping's most difficult issue since he became the country’s top leader in 2013.

In recent weeks, the Chinese yuan has hit its strongest level against the U.S. dollar since the surprise devaluation of the currency in August 2015. The yuan was trading near 6.28 per U.S. dollar Monday morning ET. The dollar is down 3.4 percent against the yuan for the year.

During his presidential campaign, Trump repeatedly said that naming China a currency manipulator would be a priority for his first day in office. But he took no immediate action and within three months of his inauguration, he reversed his position.

The has weakened sharply against the dollar after the U.S. on April 6 sanctioned several Russian oligarchs, officials, businesses and agencies, and froze assets that are under U.S. jurisdiction.

The greenback is up 8 percent against the ruble this year. The ruble traded near 62.3 against the U.S. dollar Monday morning.

The U.S. is expected to announce more sanctions on Russia for its support of Syrian President Bashar Assad. The U.S., U.K. and France conducted airstrikes in Syria over the weekend.

Markets generally expect the Federal Reserve to raise rates at least two more times this year.