U.S. stocks sold off at the open after the U.S. and China tariffs on one another's imports officially kicked in on Sept. 1.

The S&P 500 fell 0.7% to 2,907. The Dow Jones retreated 254 points, or 0.1%, to around 26,149. The Nasdaq Composite slipped 0.8% to 7,903.

Market participants dealt with lingering trade concerns after Bloomberg News reported on Monday that the U.S. and China were struggling to agree on a schedule for renewed trade talks.

President Donald Trump said both sides are still expected to meet this month. Uncertainty around the date of the U.K.'s departure from the European Union added to the market jitters.

Members of Parliament are putting forward a bill that would seek to delay the date of Brexit.

Source : Market Watch