China on Monday suspended imports from as many as 35 Taiwanese exporters of biscuits and pastries in a warning salvo to the self-governed island ahead of a potential visit to Taiwan by US House of Representatives Speaker Nancy Pelosi.

On Tuesday, Taiwan’s official Central News Agency reported that among the 3,200 Taiwanese companies registered with China’s customs under the category of food, 2,066 entries had been listed as “import suspension.”

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According to Reuters calculations based on registration data posted on the website of China’s General Administration of Customs, among the 107 entries under the category of biscuits, pastries and bread, 35 have been listed under “import suspension”.

“I learned about the ban before I got off work last night,” a business manager at one of the affected Taiwanese food producers told Reuters, adding that he did not know why his company was banned.

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“There are food companies saying their products had been rejected at China’s customs already,” he said, declining to be named.

The suspension of these food exporters come after China’s repeated warnings to Pelosi against visiting Taiwan, which it claims as its own. China’s General Administration of Customs did not immediately respond to Reuters’ request for comments.

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“We’ve noticed this and are trying to understand more about it,” a staffer of pastries maker Kuo Yuan Ye Foods told Reuters.

Reuters reported that it is unclear if more suspensions were looming. However, Taiwan’s biggest exports to China by value are electronics and parts, machinery, plastics and chemicals.

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China has already suspended the import of a slew of items, including grouper fish, pineapples and sugar apples from Taiwan since last year, citing concerns about pests, which Taiwan strongly denied.

Taiwan’s Council of Agriculture said it would take the relevant measures to help the latest companies affected by the “short-term” suspension, it said in a statement.