The broad S&P500 index fell 0.3 percent, the industry-heavy Dow Jones lost 0.6 percent and the technology-heavy Nasdaq's composite index closed at minus 0.2 percent.
The decline on the stock exchange can be attributed to US President Donald Trump's announcement that he will introduce 35 percent tariffs on goods from Canada on August 1. He has also opened up for introducing general tariffs of 20 percent.
Since April 2, a basic tariff of 10 percent applies to foreign goods that the US imports. Much higher tariffs have also been introduced on cars and car parts as well as steel and aluminum. When the 10 percent tariffs were introduced, the stock exchanges around the world plummeted. The New York Stock Exchange's S&P 500 index lost 20 percent in a few days, in one of the fastest declines ever, according to NBC.
At the same time, the EU is currently negotiating with the US about a tariff agreement.
