This undated file photo shows the Taipei 101 skyscraper in Taipei, Southeast China's Taiwan. (PHOTO / XINHUA)

The Chinese Foreign Ministry on Thursday warned the United States to refrain from any form of interference in elections in the Taiwan region to avoid causing severe damage to the China-US relationship and cross-Strait peace and stability.

"China firmly opposes the US having any form of official contact with the Taiwan region," ministry spokeswoman Mao Ning said in Beijing, after Washington said it plans to send an unofficial delegation comprising former senior officials to the region shortly after the Taiwan regional leader election this weekend.

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A senior official with President Joe Biden's administration confirmed the plan on Wednesday and said the US opposes any outside interference or influence in Taiwan's upcoming elections.

We urge the US side to earnestly abide by the one-China principle and stipulations of the three China-US joint communiques, honor the US leader's commitments with concrete actions, stop interfering in elections in the Taiwan region in any form and stop sending wrong signals to 'Taiwan independence' separatist forces.

Mao Ning, Spokeswoman for the Chinese Foreign Ministry

"The election in the Taiwan region is purely China's internal affair that brooks no foreign interference," Mao said, noting that the Taiwan question is at the very core of China's core interests and the first red line that must not be crossed in China-US relations.

The spokeswoman said China strongly deplores and firmly opposes Washington's unwarranted remarks on the elections in the Taiwan region.

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"We urge the US side to earnestly abide by the one-China principle and stipulations of the three China-US joint communiques, honor the US leader's commitments with concrete actions, stop interfering in elections in the Taiwan region in any form and stop sending wrong signals to 'Taiwan independence' separatist forces," she said.

Strong measures

China will take resolute and strong measures to safeguard its national sovereignty, security and territorial integrity, Mao added.

Also at the news briefing, Mao said Argentina has clarified to the Chinese side that media reports regarding a meeting between Argentine Foreign Minister Diana Mondino and Taipei's economic and cultural representative in the Latin American country last month "are not true".

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The Argentine side has reiterated that its new government attaches high importance to its relationship with China and firmly adheres to the one-China principle, Mao said.

"Over the past 50 years, previous Argentine governments have followed the one-China principle," she said. "China is willing to work with Argentina and constantly deepen our political mutual trust to push for the steady development of China-Argentina comprehensive strategic partnership."