Firing angry remarks at China, US lawmakers on Wednesday unveiled a plan to retaliate against countries that allegedly manipulate their currencies to snare an edge in international trade.

"The time has come for Congress to stand up for American workers and not allow China to run roughshod over the American economy. With this legislation we will finally force China to stop cheating and level the playing field for America's manufacturers," said Republican Representative Tim Murphy.

The Currency Reform for Fair Trade Act, backed by Republicans and Democrats as well as business groups and major labor unions, aims to use US anti-dumping and countervailing duties to strike back at prolonged currency manipulation.

US lawmakers have long accused Beijing of keeping the yuan, or renminbi, artificially low -- a step that would boost its exports by making Chinese products less expensive relative to US goods on global markets.

"It's time to treat illegal currency intervention like the outrageous trade subsidy it is," Republican Senator Jim Bunning said as the legislation was introduced in the Senate and House of Representatives.