China has all along opposed moves to overstretch the concept of national security, and has always upheld that trade and tariff wars have no winners, a Foreign Ministry spokesperson said in Beijing on Thursday.

Spokesperson Mao Ning made the remarks when commenting on the U.S. announcement on Wednesday that a 50 percent tariff would be imposed on imported copper, citing national security concerns.

China's position is very clear, Mao said, adding that the abuse of tariffs is in no one's interest.