BEIJING - A Chinese mainland spokesperson on Wednesday urged the United States to handle the Taiwan question with the utmost prudence.

At a regular press conference, Zhu Fenglian, spokesperson for the Taiwan Affairs Office of the State Council, reiterated that the Taiwan question remains at the very core of China's core interests and is the foremost red line that must not be crossed in China-US relations.

She urged the US side to strictly abide by the one-China principle and the provisions of the three China-US joint communiques, to stop sending the wrong signals to separatist forces, and to prevent a small handful of separatists from undermining the broader China-US relationship.

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Zhu also criticized Democratic Progressive Party (DPP) authorities in Taiwan and separatist forces for clinging to "Taiwan independence" positions and colluding with external actors in provocative attempts to seek independence.

"These are the root causes of tensions and instability across the Taiwan Strait," she said.  

Crackdown on cyberattacks

During the press conference, the spokesperson also said the mainland vows to intensify its crackdown on cyberattacks carried out by an organization of the DPP.

Police in the southern Chinese city of Guangzhou issued a wanted list in early June, naming 20 suspects accused of participating in cyberattacks launched by Taiwan's "Information, Communications and Electronic Force Command (ICEFCOM)".

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Zhu said recent law enforcement actions by mainland public security agencies represent a firm response to "Taiwan independence" separatist forces and specifically target the illicit activities of ICEFCOM.

The evidence of DPP authorities orchestrating frequent and indiscriminate cyberattacks against mainland network infrastructure through ICEFCOM is "clear and conclusive", Zhu said.

Zhu reiterated that both sides of the Taiwan Strait belong to one China and that Taiwan is an inseparable part of China. "Anyone who endangers national sovereignty, security, or development interests will face legal consequences," she added.

Zhu said that law-based actions will be taken against the DPP authorities' illegal activities, including cyberattacks conducted in collusion with external forces.

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"We will continue to take effective measures in accordance with the law to hold the perpetrators accountable. There will be no leniency," she said.

Separatists 'not allowed to profit from mainland'

The mainland will never tolerate any individuals profiting from the mainland while supporting "Taiwan independence", Zhu stressed.

She made the statement in response to recent remarks from Taiwan's die-hard separatist Shen Pao-yang about punitive measures taken by the mainland against companies linked to him.