BEIJING, April 4 (Xinhua) -- China is a "responsible investor" and respects international capital market rules, Vice Finance Minister Zhu Guangyao said Wednesday.

Zhu reiterated the stance at a press conference when asked whether China will reduce its U.S. government debt holdings as a countermeasure against proposed additional tariffs by the United States on Chinese exports.

"China manages its foreign exchange reserves via market operations in accordance with market rules, specific market principles and the principle of diversified investment," he said, citing remarks made by Chinese Premier Li Keqiang on forex reserves management last month.

To protect public assets, China also aims to keep its 3-trillion-U.S. dollar forex reserves secure, liquid and moderately profitable, Zhu said.

The U.S. administration on Tuesday announced a proposed list of products subject to additional tariffs, which covers Chinese exports worth 50 billion dollars with a suggested tariff rate of 25 percent.

China on Wednesday said it decided to impose additional tariffs of 25 percent on products worth 50 billion dollars imported from the United States, including soybeans, automobiles and chemical products.

China's foreign exchange reserves stood at 3.134 trillion dollars in February, official data showed. Its holdings of U.S. Treasury securities fell to a six-month low of 1.1682 trillion dollars in January, according to the U.S. Treasury Department.