Stocks fell at the opening bell on Monday, retreating from their record closes set last week, as investors stay rattled by ratcheting U.S.-Iran tensions.

The S&P 500 fell 0.4% to 3,221. The Dow Jones Industrial Average shed 141 points, or 0.5%, to 28,494. The Nasdaq Composite slipped 0.6% to 8,967.

President Donald Trump threatened sanctions against against Iraq after Baghdad said it could demand U.S. troops to leave the country, following the killing of Iran's top general Qassem Soleimani. After Iran's leaders vowed to hit back against the U.S., Trump also threatened to retaliate against any Iranian assault.

In company news, shares of Goldman Sachs Group Inc. and Morgan Stanley took a slight hit after news reports said the Bank of England was investigating the banks' financial reporting practices.

Source : MarketWatch