Concerns over the Covid-19 omicron variant weighed on the markets again on Monday. The Dow shed 320 points after U.K. Prime Minister Boris Johnson confirmed a patient who was infected with the strain died, and the U.S. hit the grim milestone of 800,000 Covid-19 deaths. The tech-heavy Nasdaq and S&P 500 also logged substantial losses, with travel stocks bearing the brunt of today's pullback.

Elsewhere, the Supreme Court refused a bid to block the vaccine mandate for healthcare workers in New York. Investors are also looking ahead to the Federal Reserve's two-day policy meeting that begins tomorrow. The central bank is expected to accelerate the tapering of economic stimulus, following the hottest inflation reading in nearly 40 years.

The Dow Jones Average (DJI - 35,650.95) fell 320 points or 0.9% for the day. Coca-Cola (KO) led the gainers, adding 2.6%, while Boeing (BA) paced the laggards with a 3.7% fall.

The S&P 500 Index (SPX - 4,668.97) shed 43.1 points or 0.9% for the day. Meanwhile, the Nasdaq Composite (IXIC - 15,413.28) shaved 217.3, or 1.4% for the day.

Lastly, the CBOE Volatility Index (VIX - 20.31) shed 1.6 points or 8.7% for the day.

Gold Nabs 3-Week High Despite Muted Trading Session

Oil prices finished lower on Monday, as investors continued to assess what risks the Covid-19 omicron variant pose, as well as how it may influence energy demand. January-dated crude dropped 38 cents, or 0.5%, to finish at $71.29 per barrel.

Meanwhile, gold prices settled at their highest level in three weeks, while notching their second consecutive win. The yellow metal's gains were relatively muted, however, ahead of the Fed meeting. In response, February-dated gold rose $3.50, or 0.2%, to close at $1,788.30 per ounce.