Taiwan is an inalienable part of China's territory, and the one-China principle is a prerequisite for Taiwan's participation in foreign economic cooperation, the Ministry of Commerce said on Tuesday.

The comments came after the US announced that it would sign its first agreement with the Taiwan region of China under the "US-Taiwan Initiative on 21st Century Trade".

China resolutely opposes countries having diplomatic relations with the Taiwan region in conducting official contact or exchanges in any form, including negotiation and signing of any agreement with sovereignty implication and of official nature, the ministry said.

The US side should abide by the one-China principle and the three China-US joint communiques, to fulfill its commitment of not supporting "Taiwan independence", as well as handle economic and trade relations with the Taiwan region in a prudent manner, the ministry said.