he government announced on Wednesday that it would slap anti-subsidy duties of up to 31 percent on chicken products from the United States - the move coming hot on the heels of a series of such cases initiated against the US during the past two weeks.

The Ministry of Commerce (MOC) ruled that broiler chicken products were subsidized by the US government, citing the results of an anti-dumping investigation initiated last September.

The US is the largest chicken products exporter to China, accounting for 90 percent of the 407,000 tons China imported in the first half of last year.

The rising frequency of such cases indicates that China is not shying away from initiating remedies in response to growing US trade protectionism, analysts said.

They suggest that China's "symbolic" measures - in line with rules and regulations of the World Trade Organization (WTO) - could undermine the Barack Obama administration's efforts to double exports within five years.

The latest measure came weeks before the Strategic and Economic Dialogue between the two countries, during which the value of China's currency is expected to top the agenda.

"It is notable that China has become more active and aggressive in counteracting US protectionism in line with WTO rules," said Fu Donghui, managing partner of Everbright Law Firm Beijing.

Last Thursday, the government started a 12-month anti-dumping investigation into imports of some optical fiber and chemical products from the US and the European Union. The same day, the MOC announced punitive anti-dumping duties on imports of"Nylon 6" from the US, the EU and Russia as well as the Taiwan region.

Huo Jianguo, director of the Chinese Academy of International Trade and Economic Cooperation affiliated to the MOC, called such measures a "proper response to the more aggressive trade-related investigations and charges by the US".

Last Thursday, the US Commerce Department initiated an anti-subsidy and anti-dumping investigation into Chinese aluminum extrusion manufacturers. Some US businesses have complained that China subsidizes exports of aluminum extrusions by keeping its currency much below its true value.

MOC figures show that during the first quarter of this year, 19 investigations were launched against China involving a sum of $1.19 billion, up 93.5 percent year on year. The US is in the forefront of countries in launching such probes.

Some analysts said US industries will launch more such cases as long as the yuan revaluation issue is not resolved.

However, Wang Rongjun, a professor at the Institute of American Studies at the Chinese Academy of Social Sciences, ruled out a "trade war" between China and the US, saying bilateral economic and trade relations are stable.

China "should go to the WTO and fight back with more trade remedies" to protect its interests, said a professor at the Trade Research Institute affiliated to the MOC, who declined to be named.

He likened the latest moves by both sides to a "chess game" to test each other's limits before they start finding a solution to the yuan issue.

Earlier this month, the US delayed a report due out in mid-April on whether to label China a currency manipulator.

China is under growing pressure to let the yuan appreciate. Emerging markets including Brazil and India recently joined the US in urging Beijing to allow the yuan to rise to "help rebalance the world economy".