The duties will increase by more than five-fold the import prices on China’s cold-rolled flat steel products, which totalled US$272.3 million last year. The steel is primarily used in automotive body panels, appliances, shipping containers and construction.

The ruling by the Commerce Department comes amidst escalating US-China trade tensions, particularly in the steel sector where both US and European producers claim China is distorting world pricing by dumping its excess output abroad as demand at home wanes.

Chinese companies affected by the duties include Baosteel Group, Angang Group Hong Kong Holdings Ltd, and Benxi Iron and Steel (Group) Special Steel.

Commerce has also upheld its preliminary anti-dumping duties of 265.79 percent, but increased its preliminary anti-subsidy duties to 256.44 percent from 227.29 percent.

In a separate case, US Steel is seeking to stop all imports from China’s top steelmakers. The US steelmaker called on regulators to investigate dozens of Chinese producers and their distributors for allegedly conspiring to fix prices, stealing trade secrets and circumventing trade duties by false labelling.

Beijing has defended itself against the allegations, saying it has done enough to reduce steel capacity and blaming global excess and weak demand for the industry's woes.