BEIJING - China's Foreign Ministry on Monday slammed US Health and Human Services Secretary Alex Azar's ongoing visit to Taiwan, urging the US side to stop official interactions and contact of all kinds, as well as the upgrading of substantive relations with the island. 

The spokesperson reiterated that the Taiwan question is the most important and sensitive issue in China-US relations, and the one-China principle is the political foundation of the bilateral relationship

The remarks were made by Foreign Ministry spokesperson Zhao Lijian when responding to a query about Azar's ongoing visit at a press briefing held in Beijing.

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"China is consistently and firmly opposed to the official interactions between the United States and Taiwan, and we have lodged stern representations with the US side," Zhao said.

The spokesperson reiterated that the Taiwan question is the most important and sensitive issue in China-US relations, and the one-China principle is the political foundation of the bilateral relationship.

"The US move is a serious breach of its commitments pledged on the Taiwan question," said Zhao.

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"We urge the US side to abide by the one-China principle and the provisions of three China-US joint communiques, stop official interactions and contact of all kinds as well as the upgrading of substantive relations with the island, and handle Taiwan-related issues in a prudent and proper manner, so as not to seriously damage China-US cooperation in major areas as well as peace and stability across the Taiwan Straits," Zhao added.