(Bloomberg) -- The European Union risks shaking foundations of its relations with China if it continues high-profile engagement with Taiwan and pushes for a bilateral investment agreement, a senior Chinese diplomat said Wednesday.

“The one-China principle is a red line for us,” Fu Cong, China’s ambassador to the EU, said in remarks at the European Policy Center think tank, reminding the audience of commitments the bloc made related to Taiwan in 1975. 

“If these commitments actually were violated, this will fundamentally change, will shake the foundations of our bilateral relationship,” he said. “So I want to draw the attention of our EU partners to the seriousness of this issue. We are seeing some erosion of these basic commitments.”

Fu, who arrived in Brussels at the end of last year, said that while the focus of his mission is to improve political environment between China and the EU, he wants to see some tangible results, promoting trade and economic ties. He also warned against allowing issues like disagreements on human rights to spill over into other areas of the bilateral relationship.

His remarks follow a phone call that the Czech Republic’s incoming president Petr Pavel held last month with Taiwan leader Tsai Ing-wen, saying later that China is “definitely not a friend” and is being “assertive” in seeking to shift the balance of geopolitical relations. The EU has been reassessing its relationship with China, which is increasingly viewed by the 27-member bloc as more of a rival and competitor on issues ranging from trade to human rights.

Fu brushed off accusations that China is being assertive, but he added that Beijing is now speaking in “clearer terms” on what has been its position in the past decades, and that each time it takes a strong position it is in “response to a provocation from the other side.” He said China is not trying to block Taiwan, which is looking to expand cooperation on key technologies like semiconductors, but will not accept its investment treaty with the EU or anything else that implies Taiwan has national sovereignty.

As for China’s comprehensive agreement with the EU on investment, Fu said China encourages foreign investment to return and called for mutual sanctions to be lifted simultaneously.

Relations between the EU and its largest trading partner reached a high point at the end of 2020 when the two sides signed a long-awaited investment treaty, but quickly deteriorated after the EU sanctioned Chinese officials over accusations of human rights abuse in Xinjiang. China responded by placing sanctions on European lawmakers, academics and others, leading the bloc to freeze the investment deal. 

“If for whatever reason lifting sanctions simultaneously may not apply now, we are also open to other initiatives,” Fu said. “Give us some proposals and we are ready to study them.”

He said that China’s relations with the EU and Russia are both multifaceted, and while it supports Ukraine’s territorial integrity, its contacts with Moscow do not need to be dominated by one issue. He said he will not be surprised if China’s President Xi Jinping visits Moscow, though no such plan has yet been officially announced.

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