Beijing: China on Thursday warned the US against the House of Representatives Speaker Nancy Pelosi's upcoming visit to Taiwan next month saying that it will act strongly and take countermeasures if the US side insists on going ahead with the visit.

"China will act strongly to resolutely respond to US House Speaker Nancy Pelosi's planned trip to Taiwan and take countermeasures should the US side insist on making the visit," Xinhua quoted Chinese foreign ministry spokesperson Wang Wenbin as saying.

"If Speaker Pelosi visits Taiwan, it would seriously violate the one-China principle and the stipulations in the three China-US joint communique and harm China's sovereignty and territorial integrity," Wang added.

He said that it will have a severe negative impact on the political foundation of China-US relations, and send a gravely wrong signal to "Taiwan independence" separatist forces.

The Chinese side has repeatedly stated its stern position on firmly opposing Pelosi's visit to Taiwan, Wang said adding that the US Congress is part of the US government, and is supposed to strictly adhere to the US commitment on the Taiwan question.

"Should the US side insist on making the visit, China will act strongly to resolutely respond to it and take countermeasures. We mean what we say," Wang reiterated.

Beijing's opposition came after a US media report said that the US House of Representatives plans to visit Taiwan in August amid tension with China. As per a media report, Pelosi and her delegation will also visit Indonesia, Japan, Malaysia and Singapore, and spend time in Hawaii at the headquarters of the US Indo-Pacific command.

Meanwhile, US President Joe Biden on Wednesday said the US military believes it is not a "good idea" for House of Representatives Speaker Nancy Pelosi to travel to Taiwan as planned.

Pelosi is reportedly planning to visit Taiwan in August, but the White House said her plans have not been locked in yet.

China has strongly opposed US House Speaker Nancy Pelosi's upcoming visit to Taiwan next month amid concerns over cross-strait ties following Russia's invasion of Ukraine.

"The military thinks it's not a good idea right now," Biden said on Wednesday as quoted by the White House press pool.

Chinese Foreign Ministry spokesperson Zhao Lijian said the Chinese side has stated on many occasions that it is firmly opposed to any form of official interaction between the United States and the Taiwan region.

"If Speaker Pelosi visits Taiwan, this would gravely violate the one-China principle and the stipulations of the three China-US joint communique, seriously undermine China's sovereignty and territorial integrity, severely impact the political foundation of China-US relations and send a seriously wrong signal to 'Taiwan independence' secessionist forces," Zhao said.

According to a Chinese state media outlet, "If the news is true and the trip happens, it will be one of the most egregious provocations by the US to China on the Taiwan question since the establishment of diplomatic relations between China and the US."

A Global Times editorial said visiting Taiwan is definitely a red line that Pelosi must never cross. "China is resolute in defending national sovereignty and territorial integrity, and has the right to take forceful measures against "Taiwan independence" secessionist forces and extraterritorial forces at any time in accordance with changes in the situation, including against the trip and Pelosi herself," the state outlet said.

Back in April, Nancy Pelosi's visit to Taiwan had been postponed after she tested positive for COVID-19. At that time, Beijing had resolutely opposed any official exchange between the United States and Taiwan.

This latest visit comes after China asked the US to immediately cancel a potential sale of military-technical assistance to Taiwan worth an estimated USD 108 million.

Chinese Foreign Ministry spokesperson Wang Wenbin said the US arms sales to China's Taiwan region seriously violate the One-China principle and the three China-US joint communique, particularly the August 17 communique, and gravely undermine China's sovereignty and security interests.

China, which regards Taiwan as its province despite decades of separate governance, has earlier strongly opposed military cooperation between Washington and Taipei.

This defence agreement between the US and Taiwan came after Chinese Foreign Minister Wang Yi said the One-China principle is what underpins stability across the Taiwan Strait and warned of "ferocious storms" across the region if the principle is "arbitrarily challenged or even sabotaged."