BEIJING, Jan. 14 (Xinhua) -- China on Monday expressed stern opposition to participation by the United States and other countries in Taiwan's submarine production project.

Foreign Ministry spokesperson Hua Chunying made the remarks when responding to media reports saying the United States has permitted some of its military enterprises to export technology to help Taiwan build submarines.

Enterprises from the United States, Europe, Japan and India have reportedly demonstrated their interest to take part in the project.

China's firm opposition to any countries' arms sales and military relations with Taiwan in any forms is consistent and clear-cut, Hua stressed at a regular press briefing.

"We urge the United States and other relevant countries to fully understand how sensitive and harmful this matter is," Hua added.

She urged these countries to adhere to the one-China principle and not to allow their enterprises to take part in Taiwan's submarine manufacture project in any forms.

They must stop any forms of military ties with Taiwan, deal with Taiwan-related issues properly and cautiously to avoid severely jeopardizing relations with China as well as peace and stability in the Taiwan Strait, she said.