Czech Senate speaker Milos Vystrcil will “pay a heavy price” for making an official trip to Taiwan and China will not sit idly by, the Chinese government’s top diplomat said on Monday, in a warning brushed off by Taiwan’s government.

Vystrcil arrived in Taipei on Sunday on a visit to promote business links with Taiwan, saying the Czech Republic would not bow to Beijing’s objections.

Speaking while in Germany, Chinese State Councillor Wang Yi said there would be retribution.

“The Chinese government and Chinese people won’t take a laissez-faire attitude or sit idly by, and will make him pay a heavy price for his short-sighted behaviour and political opportunism,” China’s Foreign Ministry cited Wang as saying.

Wang said the Chinese government and people will not tolerate such “open provocation” by Vystrcil and the anti-China forces behind him, though gave no details of how exactly Beijing would react.

Speaking in Taipei, Taiwan Economics Minister Wang Mei-hua brushed off the criticism, though declined direct comment on China’s attack on Vystrcil.

“The Czech Republic and Taiwan are free and democratic countries which put great store on human rights. We have the same values as the Czechs,” she told reporters, speaking before a joint business forum.

Vystrcil did not directly address China’s criticism of his visit in a brief speech at the same event, talking instead about how he was aiming to boost business relations.

“Freedom and democracy are the main basis of prosperity,” he said, speaking through an interpreter.

Vystrcil is due to meet Taiwan President Tsai Ing-wen later in his trip and will address Taiwan’s parliament before leaving on Friday.

China considers Taiwan a breakaway province ineligible for state-to-state relations.

Czech President Milos Zeman has sought closer business and political ties with China since taking office in 2013, but his efforts have been hit by failed investment plans and Czech wavering about allowing China’s Huawei Technologies to play a role in developing next-generation telecoms networks.