China strongly opposes US anti-dumping and anti-subsidy investigations into steel tubes and woven sacks imported from China, a spokesman with the Ministry of Commerce said on Friday.

The US Department of Commerce announced this week it would officially launched the investigations into imports of light-walled rectangular pipes and tubes and laminated woven sacks used to package dog food, bird seed and other products.

In June, 12 US steel manufacturers and the US Laminated Woven Sacks Committee complained to the US government of unfair pricing of steel pipes and woven sacks imported from China.

"The US government continues the mistake of imposing anti-dumping and anti-subsidy measures from time to time," Wang Xinpei said.

In March and June, the US Department of Commerce (DOC) started anti-dumping and anti-subsidy investigations into Chinese coated free sheet paper and carbon steel tubes.

"These investigations have aroused strong dissatisfaction in Chinese business circles," Wang said.

Wang said that as the US did not treat China as a market economy, the use of anti-dumping and anti-subsidy measures also infringed US rules and its tradition of not adopting anti-subsidy measures against non-market economies, which had been practiced for more than two decades.

Wang said the move threatened Sino-US economic and trade ties and China would assert its rights as a WTO member if the United States maintained the measures.