U.S.-listed Chinese companies traded mostly lower on Monday, with 7 of the top 10 stocks by weight in the S&P U.S. Listed China 50 index ending the day on a downbeat note, as the country's political uncertainty continued to weigh on the market.

Shares of Baidu, Inc. and shares of Alibaba, tumbled 3.64 percent and 2.87 percent respectively, leading the laggards in the top 10 stocks of the index, while shares of BeiGene, Ltd. jumped 3.45 percent as the biggest advancer among the 10 stocks.

Meanwhile, shares of JD.com, another China's e-commerce giant listed in the U.S. equity market, fell 1.82 percent to 44.15 U.S. dollars apiece on Monday.

U.S. stocks suffered big losses on Monday, with the all three major indices dropping over 1.3 percent, as investors continued to monitor the latest political developments in the White House.

U.S. President Donald Trump on Sunday accused Special Counsel Robert Mueller of hiring "hardened Democrats" to investigate alleged ties between his 2016 presidential campaign and Russia.

Trump's words raised market concerns of another shakeup in the senior ranks of the administration following last week's turmoil.

At the close, the Dow Jones Industrial Average decreased 335.60 points, or 1.35 percent, to 24,610.91. The S&P 500 fell 39.09 points, or 1.42 percent, to 2,712.92. The Nasdaq Composite Index fell 137.74 points, or 1.84 percent, to 7,344.24.

The CBOE Volatility Index, widely considered the best fear gauge in the stock market, surged 20.38 percent to 19.02 on Monday.