US President Donald Trump has accused Russia and China of devaluing their currencies at a time when the US was raising interest rates.
"Russia and China are playing the Currency Devaluation game as the US keeps raising interest rates. Not acceptable!" Trump said in a Twitter post on Monday, Efe news reported.
Last month, the US Federal Reserve raised short-term interest rates to a range of 1.5 per cent to 1.75 per cent due to the solid economic growth in the US, and additional rate hikes are expected this year.
In its semi-annual report, released last week, the US Treasury Department chose not to describe China as a foreign exchange manipulator.
In the past few weeks, Trump has announced a series of protectionist measures, including the imposition of tariffs on steel and aluminium imports, and has mentioned special tariffs on a number of products imported from China.
Trump said the goal was to reduce the huge US trade deficit with China.
China responded by announcing tariffs on some US imports, causing alarm in global markets about a possible trade war between the countries.
China's currency, the yuan, has climbed roughly 10 per cent against the dollar over the past 12 months, while the Russian ruble has lost 10 per cent against the greenback against the backdrop of US and European Union economic sanctions against Moscow.
Russia is not among the dozen most-important US trade partners.