SHENZHEN (Reuters) – China’s COVID-19 restrictions will hinder foreign investment in the country over the long-term as travel limits and other limitations block projects from flowing through the pipeline, warned the American Chamber of Commerce President on Tuesday.

While there are no signs of American firms leaving China, Michael Hart stated that the long-running process of due diligence and research has not been halted.

He said that he was concerned about U.S. investments in China, as Chinese people are unable to travel.

“Unfortunately, the COVID lockdown for this year, and the restrictions over the past two years, are going to mean that three, four, or five years down the road, investment will be declining most likely.”

Although coronavirus restrictions have been lifted in many parts of the globe, China insists that it is essential to maintain a zero COVID policy. This prevents the country from becoming overwhelmed by its health resources.

Hart stated that the restrictions have also led foreign supply chain companies in China to seek alternative sources of disruption.

In the report, U.S. business leaders cited concerns about market access restrictions as well as discriminatory regulations.

A flash survey was released by the chamber last week, warning of an exodus in foreign staff from China as a result of the ongoing COVID restrictions and lockdowns. The report stated that 58% had reduced their revenue projections this year.

European business are prepared for the disruption caused by COVID, according to the European Chamber of Commerce in China on Monday. The chances of an improvement in the situation will be slim until China improves its vaccination rates.