A senior Chinese trade official said on Thursday that the five combined anti-dumping and anti-subsidy investigations launched by the United States against Chinese goods violate World Trade Organization (WTO) rules.

Addressing a news conference held by the State Council Information Office, Vice Minister of Commerce Gao Hucheng said the investigations and the measures the United States might take against Chinese goods would lead to double taxation, which was prohibited by the WTO.

The investigations involved 635 enterprises with 70,000 workers and goods worth US$ 860 million, Gao said, adding five dual investigations in less than a year was unprecedented.

The US Department of Commerce decided in late July that it would launch anti-dumping and anti-subsidy probes simultaneously into China-made off-road tyres.

The probe followed dual investigations into China-made coated free sheet paper in March, carbon steel tubes in June, and light-walled rectangular pipes and tubes, and laminated woven sacks in July.

China's foreign trade has increased by 29 percent annually for the last five years while the country's exports were up 30 percent annually, which resulted in more trade friction, said Gao.

According to the MOC, 869 anti-dumping, anti-subsidy and combined cases have been launched against China since 1979, including 136 raised by the United States.

As the United States did not treat China as a market economy, the use of anti-dumping and anti-subsidy measures infringed US rules and its tradition of not adopting anti-subsidy measures against non-market economies, Gao said.

Moreover, the United States included loans from Chinese commercial banks as government subsidies, showing how little the US knew about Chinese commercial banks, said Gao.

China, including the government, industry association and enterprises would work in a united response, Gao said without elaborating.

At the news conference, Assistant Minister of Commerce Wang Chao said that if the US stopped Chinese goods, imports from other countries may be more expansive.

US consumers saved more than US$ 600 billion by buying products made in China in the last ten years, said Gao.

Research by the US-China Business Council shows bilateral trade cooperation is expected to add US$ 1,000  to the disposable income of each US family in 2010.