A proposal by a U.S. congressional panel to ban Chinese state-owned enterprises from buying U.S. firms was "hawkish" toward China, an American think tank said Friday, amid concerns over U.S. President-elect Donald Trump's protectionist stance.

Chinese state-backed companies should be prohibited from "acquiring or gaining effective control of U.S. companies" because they are used by Beijing "as a tool to pursue social, industrial, and foreign policy objectives," the U.S.-China Economic and Security Review Commission said Wednesday in its annual report to Congress.

The commission is tasked with monitoring trade and security links between the two countries.

The report shows "a hawkish stance on China," said Daniel Rosen, founding partner of research company Rhodium Group, at a news conference in Beijing. "It's a very difficult suggestion to actually implement," he said.

The commission's proposal came after Trump's election earlier this month as the next U.S. president sparked wide concerns over the future of Sino-U.S. economic relations because of his endorsement of trade protectionism during his campaign. Trump has promised to label China a currency manipulator and impose a punitive 45% tariff on Chinese imports.

The world's two largest economies have developed closely intertwined interests over the past 25 years with China's reform and opening-up.

Their investment ties are even deeper than official figures have indicated, according to a study led by New York-based Rhodium and the National Committee on U.S.-China Relations released on Monday.

The study found that American investors had funneled $228 billion into China between 1990 and 2015, more than three times that recorded by the U.S. Bureau of Economic Analysis. China invested more than $64 billion in the United States during the period, 56% more than official Chinese data showed.

China's Foreign Ministry on Thursday blasted the commission's report as "again revealing the commission's stereotypes and prejudices."

"We have always encouraged Chinese companies to abide by local laws and regulations and make overseas investment based on market principles," ministry spokesman Geng Shuang said at a briefing.

"We hope that countries will create a fair and healthy environment for investment by Chinese companies," he said.

Contact reporter Fran Wang (fangwang@caixin.com); editor Calum Gordon (calum@caixin.com)