The CBOE Volatility Index .VIX , a barometer of expected near-term stock market volatility, closed at its highest since the election.
The yen held steady against the dollar, taking a breather after having risen on Wednesday to its highest level in almost eight weeks. Following Trump's remarks, North Korea on Wednesday said it was "carefully examining" plans for a missile attack on the U.S. Pacific territory of Guam, which is home to a large U.S. military base. Away from the geopolitical drama, USA inflation data is due at 1330 GMT.
The answer to this is naturally impossible to answer, because if we knew, the markets would already be reacting. "The strong global economy driven by strong earnings is really helping to minimize some of these concerns".
Similar to the S&P 500, the Nasdaq Composite Index and the Dow Jones Industrial Average also started the day lower and trended lower on August 10.
The MSCI World index slipped 0.15 percent, extending Thursday's 1.1 percent drop, its biggest one-day slide since May 17.
Asian stocks slumped on Friday as tensions ramped up between the USA and North Korea, sending investors into less risky assets such as gold, the yen and U.S. government bonds.
Tata Steel agrees deal to restructure British pension fund
Tata has agreed a final payment of £550m, and will also give the pension scheme a 33% stake in its United Kingdom business. The British Steel Pension Scheme said it would write to its members in the next few weeks about the new scheme.
The US-North Korea spat that allowed safe havens to rally this week continued during today's European session. The Nasdaq added 39.68 points, or 0.6 percent, to 6,256.56. This week has been its biggest rise since June 2016.
South Korea's KOSPI fell 1.8 per cent to an 11-1/2-week low, but its losses for the week are a relatively modest 3.2 per cent.
United Kingdom mid cap stocks also came under pressure, falling 0.8 percent as shares in Dixons Carphone slumped more than 7 percent to its lowest level since the aftermath of the Brexit vote last June, driven down by a double downgrade from a star broker.
The yen tends to benefit during times of geopolitical or financial stress as Japan is the world's biggest creditor nation and there is an assumption that Japanese investors there will repatriate funds should a crisis materialise. By 2.50pm, it was trading down 0.1%. The euro rose to $1.1812 from $1.1774. Yields on core government debt fell.
The broader United Kingdom mining sector fell 2.7 percent.
Benchmark U.S. crude rose 23 cents to settle at $48.82 a barrel on the on the New York Mercantile Exchange. It is drifting towards the lows from last month against the dollar.
The dollar index .DXY , which tracks the greenback against six rival currencies, was down 0.12 percent to 93.53, after rising as high as 93.888 earlier in the session.
Spot gold prices were unchanged at $1,286.27 a ounce, after touching a two-month high earlier.
J.C. Penney sank 16.6 percent after the struggling department store chain reported quarterly results that fell short of Wall Street's expectations.