* Russian stock market, bonds and currency plunge
* Crude prices up more than 2 percent
* Gold stocks rise, tracking the metal's price move
* Indexes down: Dow 1 pct, S&P 0.8 pct, Nasdaq 1 pct
U.S. stocks fell on Monday alongside other risk assets globally as Ukraine and Russia prepared for possible war after Russian President Vladimir Putin declared he had the right to invade his neighbor.
Ukraine mobilized for war on Sunday and Washington threatened to isolate Russia economically as Moscow's biggest confrontation with the West since the Cold War unfolded.
The S&P 500 had closed at a record high on Friday, and profit-taking was expected on Wall Street due to the political uncertainty.
"There's been a very significant rally," said Rick Meckler, president of investment firm LibertyView Capital Management in Jersey City, New Jersey. "If you need an excuse to sell, this is a good one."
Russian stocks and bonds fell sharply and the central bank hiked interest rates to defend the ruble. The MICEX index of Moscow stocks tumbled 11 percent to 1,288.81. The dollar-denominated RTS stock index tumbled 12 percent.
The Market Vectors Russia ETF fell 7 percent in heavy volume, hitting a session low of $22.16, its lowest in 4-1/2 years.
Energy stocks could lose if relations between the United States and Russia deteriorate further. Volatility will likely spike alongside the uncertainty of the situation.
"Anything that involves a boycott of Russian supplies, which are very significant, could impact the energy sector dramatically," said Meckler.
"In situations like this, you see very quick reactions reverse as people understand the scenario and how things play out."
The initial reaction in energy stocks was on the upside, however, as both Brent and U.S. crude prices rose more than 2 percent each.
The Dow Jones industrial average fell 160.16 points or 0.98 percent, to 16,161.55, the S&P 500 lost 15.52 points or 0.83 percent, to 1,843.93 and the Nasdaq Composite dropped 41.87 points or 0.97 percent, to 4,266.249.
Gold prices hit a four month high as investors sought safe-haven assets, boosting gold stocks. U.S.-traded AngloGold Ashanti shares gained 3.7 percent to $18.23.
Though the focus will likely remain on Ukraine, the economic calendar was busy on Monday. U.S. consumer spending rose more than expected in January, likely as chilly weather boosted demand for heating. Separate data showed U.S. manufacturing growth rebounded off an eight-month low in February, helped by a recovery in new orders, and construction spending unexpectedly rose in January.