China has imposed further sanctions on Hsiao Bi-khim, Taiwan’s de facto ambassador to the United States, prohibiting her and family members from entering the mainland, Hong Kong and Macau, state media reported on Friday.

The sanctions announced by China’s Taiwan Affairs Office also ban investors and firms related to Hsiao from cooperating with mainland organisations and individuals.

They come after Taiwanese President Tsai Ing-wen’s meeting with US House Speaker Kevin McCarthy during a stopover in the United States this week.

“Wow, the PRC (People’s Republic of China) just sanctioned me again, for the second time,” Hsiao tweeted in response to the announcement.

China’s Foreign Ministry also announced steps against the United States’ Hudson Institute and Reagan Library and their heads, saying both institutions provided a platform and facilities for what it called Tsai’s separatist activities.

Taiwan’s Foreign Ministry reacted angrily, saying China had no right to “butt in” when it came to Tsai’s overseas trips and that Beijing was “deceiving itself” if it thought the sanctions would have any effect.

“It not only deepens our people’s antipathy but exposes the irrational and ridiculous nature of the communist regime,” it said.

China considers Taiwan its own territory and not a separate country. Taiwan’s government disputes China’s claim.

The Chinese foreign ministry said it has immediately restricted universities, institutions, and other organisations and individuals in China from engaging and cooperating with the Hudson Institute and Reagan Library and their leaders.

China has also banned the leaders from entering the country, and frozen any properties they have in China, it said.

Hudson Institute in a statement said it was proud to host Tsai and that it stands “firmly with Taiwan and against the CCP,” referring to the Chinese Communist Party.

The Reagan Library did not immediately respond to a request for comment.

Chinese sanctions will have little practical impact as senior Taiwanese officials do not visit China while Chinese courts do not have jurisdiction in Taiwan.

China imposed similar sanctions on The Prospect Foundation, which is headed by a former Taiwanese foreign minister, and the Council of Asian Liberals and Democrats, a multinational alliance that Taiwan’s ruling Democratic Progressive Party (DPP) co-founded in 1993.

China’s Taiwan Affairs Office accused the institutions of promoting the idea of “Taiwan independence” internationally.

The Prospect Foundation expressed “strong regret” at the decision, saying in a statement that it would “still uphold the spirit of academic independence and the principle of defending Taiwan’s sovereignty”.

The Council of Asian Liberals and Democrats said the sanctions were “unfortunate” but that it stands by its programmes and activities to advance democracy, human rights and rule of law for everyone in Asia.

Last August, after then- US House Speaker Nancy Pelosi visited Taiwan, China imposed sanctions including an entry ban on seven Taiwanese officials and lawmakers including Hsiao, whom it accused of being “independence diehards,” drawing condemnation from the democratically governed island.

Others on the August sanctions list include Taiwan Foreign Minister Joseph Wu; Wellington Koo, Secretary-General of Taiwan’s National Security Council; and DPP politicians.

DPP lawmaker Chao Tien-lin told reporters at parliament the sanctions on Hsiao were “absurd.”

“This will have no impact on her,” he said.