The conference, which begins on Monday, is being held by the Inter-Parliamentary Alliance on China, a group of hundreds of lawmakers from 35 countries concerned about how democracies deal with Beijing.
Lawmakers from at least six countries, including three in Europe, said Chinese diplomats were pressuring them not to attend a conference in Taiwan, in what they described as efforts to isolate the self-governed island.
Politicians in Slovakia, North Macedonia, Bosnia and Herzegovina, as well as Bolivia and Colombia, said they were getting texts, calls and urgent requests for meetings that would conflict with their plans to travel to Taipei.
The conference begins on Monday and is being held by the Inter-Parliamentary Alliance on China (IPAC), a group of hundreds of lawmakers from 35 countries concerned about how democracies approach Beijing.
IPAC has long faced pressure from the Chinese government and some members have even been sanctioned by Beijing. In 2021, the group was targeted by Chinese state-sponsored hackers, according to a US indictment unsealed earlier this year.
But Luke de Pulford, the alliance's director, said the pressure from Chinese officials in the past few days has been unprecedented, calling it "gross foreign interference."
"How would PRC officials feel if we tried to tell them about their travel plans, where they could and could not go?" he said.
"It's absolutely outrageous that they think that they can interfere in the travel plans of foreign legislators."
During past IPAC meetings in other locations, lawmakers were approached by Chinese diplomats only after they concluded. This year, the first in which IPAC's annual meeting is taking place in Taiwan, there appeared to be a coordinated attempt to stop participants from attending.
"I’m Wu, from Chinese Embassy," read a message sent to Antonio Miloshoski, a member of parliament in North Macedonia.
"We heard that you got an invitation from IPAC, will you attend the Conference which will be held next week in Taiwan?"
In some cases, lawmakers described vague inquiries about their plans to travel to Taiwan. In other cases, the contact was more menacing. One lawmaker said that Chinese diplomats messaged the head of her party with a demand to stop her from going.
"They contacted president of my political party, they ask him to stop me to travel to Taiwan," said Sanela Klarić, a member of parliament in Bosnia and Herzegovina.
"They're trying, in my country, to stop me from traveling. This is really not OK."
China routinely threatens retaliation against politicians and countries that show support for Taiwan, which has only informal relations with most countries due to Chinese diplomatic pressure.
Klarić said the pressure was unpleasant but only made her more determined to go.
"I really am fighting against countries or societies where the tool to manipulate and control people is fear," she said, adding that it reminded her of threats and intimidation she faced in the war in Bosnia in the 1990s.
"I really hate the feeling when somebody is frightening you," she said.
Last week, Beijing criticized Taiwan for holding its annual Han Kuang military drills, saying that the ruling Democratic Progressive Party was "carrying out provocations to seek independence."
"Any attempt to whip up tensions and use force to seek independence or reject reunification is doomed to failure," Chinese Foreign Ministry spokesperson Mao Ning told reporters at a press conference in Beijing.
China has been peeling off the island's diplomatic allies, often with promises of development aid, in a long-running competition between the two that has swung in Beijing’s favour in recent years.
The Pacific Island nation of Nauru switched recognition to Beijing earlier this year, a move that reduced Taiwan's dwindling number of official diplomatic allies to just 12.
But what has been perceived to be China's sometimes heavy-handed approach has also alienated other countries.
In 2021, Beijing downgraded relations and blocked imports from Lithuania, a member of both the EU and NATO, after the Baltic nation broke with diplomatic custom by agreeing that a Taiwanese representative office in its capital of Vilnius would bear the name Taiwan instead of Chinese Taipei, which other countries use to avoid offending Beijing.
The following year, the EU adopted a resolution criticising Beijing's behaviour toward Taiwan and took action against China at the World Trade Organization over import restrictions.
Most of the lawmakers targeted appear to be from smaller countries, which de Pulford said was likely because Beijing "feels that they can get away with it."
But he added that the coercive tactics have only made participants more determined to take part in the summit.
Miriam Lexmann, a Slovakian member of the European Parliament whose party head was approached by Chinese diplomats, said the pressure underscored her reason for coming to Taiwan.
We want to "exchange information, ways how to deal with those challenges and threats which China represents to the democratic part of the world, and of course, to support Taiwan," she said.
The Chinese Foreign Ministry did not respond to a request for comment.