US stock markets settled lower on Monday, led by the energy sector as oil prices dropped, while investors awaited the next run of major earnings reports and sought further clarity on President Donald Trump's economic policies.

The Dow Jones Industrial Average declined 19.04 points or 0.09 percent to settle at 20,052.42. The broader S&P 500 index declined 4.86 points or 0.21 percent to end at 2,292.56.

On the other hand, NASDAQ 100 index gained 6.37 points or 0.12 percent to close at 5,167.96.