BEIJING, March 4 (Xinhua) -- China is strongly dissatisfied with and firmly opposes the U.S. decision to impose an additional 10-percent tariff on goods imported from China again, a spokesperson for the Ministry of Commerce said Tuesday.China will take countermeasures to firmly safeguard its own rights and interests, the spokesperson said.China is one of the countries with the strictest and most rigorously enforced anti-drug policies in the world. China and the United States have engaged in extensive and in-depth anti-drug cooperation, achieving remarkable results, the spokesperson noted.However, the United States has repeatedly shifted the blame and imposed additional tariffs on Chinese exports to the country, citing the issue of fentanyl as a pretext."What the U.S. side has done is a typical act of unilateralism and bullying in disregard of facts, international trade rules and the voice of all parties," the spokesperson said.