"European shares are. continuing their slide on the back of ever more increasing tensions between North Korea and the USA", added analyst Markus Huber at City of London Markets. The S&P 500 closed 0.24% lower at 2,474.92, with materials leading decliners.
Consumer-focused stocks, media companies and banks accounted for much of the market decline.
At home, the Footsie rose marginally in the previous session, having added 10.79 points to end the session 0.14 percent higher at 7,542.73, finding support in strong energy shares, which helped offset a drop in InterContinental Hotels Group (LON:IHG) and Paddy Power Betfair (LON:PPB), whose results disappointed investors.
Late in the session, U.S. President Donald Trump said perhaps his threat to unleash "fire and fury" on North Korea "maybe wasn't tough enough". Small-company stocks fell more than the rest of the market.
The biggest risers on the FTSE 100 Index were Smurfit Kappa up 38p to 2,224p, Persimmon up 39p to 2,501p, DCC up 70p to 6,885p, Barratt Developments up 6p to 595.5p.
The local currency was trading at 1,137.90 won against the USA dollar, down 2.70 won from the previous session's close.
Nvidia's quarterly revenue in its data center and automotive businesses missed estimates, dragging the chipmaker's shares down 8.6 percent.
The indicated USA market moves reflect a selloff across global stock markets Friday.
The major averages all closed in positive territory, although the tech-heavy Nasdaq outperformed its counterparts. It rose $15.70, or 1.2 percent, to $1,277.80 an ounce.
In overseas trading, stock markets across the Asia-Pacific region saw continued weakness during trading on Friday.
The Labor Department said its producer price index for final demand edged down by 0.1 percent in July after inching up by 0.1 percent in June. With one session left to go, the S&P 500 was headed for a weekly drop of around 1.6%, which would be its biggest since a fall of 1.9% for the week ended November 4, 2016.
In the United Kingdom, the stock of TV giant ITV was down 1.9 percent in early trading, and Sky shares were down 0.5 percent, while Germany's ProSiebenSat.1 fell 1.2 percent. European stocks were facing the worst week in nine months (http://www.marketwatch.com/story/european-stocks-face-worst-week-in-9-months-on-us-north-korea-tensions-2017-08-11) on U.S. Wholesale gasoline dropped 2 cents to $1.60 a gallon, while heating oil shed 2 cents to $1.63 a gallon.
South Korea's benchmark Kospi index lost 1.1 per cent. Copper fell 2 cents to $2.93 a pound.
CURRENCIES: The dollar fell to 109.96 yen from 110.48 yen late Tuesday. The euro held steady at $1.1752.