Late in the afternoon, Trump told reporters that his "fire and fury" warning to North Korea may not have been tough enough.
The remarks followed a new report asserting that USA intelligence has assessed that Pyongyang has successfully produced a nuclear warhead that can fit inside its missiles.
The Korean won continued to fall versus the dollar, down 0.13 per cent to 1,143.5 on Friday for a 1.6 per cent decline on the week.
"If the data continues to come in on the softer side, the market might start to price the Fed staying on hold this year", said Sireen Harajli, FX strategist at Mizuho in NY.
About 15 minutes into trading, the Dow Jones Industrial Average had dropped to 21,947.15, down 0.5 percent from Wednesday's close, falling back below the 22,000 mark it first broke through on August 2.
Bond prices were little changed.
Benchmark 10-year notes last rose 5/32 in price to yield 2.194 percent, from 2.211 percent late on Thursday.
Travel website operator Priceline fell 7.26 percent, weighing the most on the S&P and the Nasdaq, following a disappointing forecast. The stock fell $3.30 to $30.09.
Retailers Wal-Mart (WMT), Home Depot (HD), Target (TGT), Staples (SPLS), and Gap (GPS) are also among the companies due to report their quarterly results next week.
Biotechnology, tobacco, and transportation stocks also saw considerable strength, while steel stocks extended a recent move to the downside.
The Labor Department also said unit labour costs rose by 0.6% in the second quarter following an upwardly revised 5.4% spike in the first quarter.
Away from geopolitics, Graham Bishop, investment director at Heartwood Investment Management, said price action overall has been muted when companies have beat estimates in the latest reporting period, but then "altogether painful" when they miss. The stock was the biggest gainer in the S&P 500, adding $8.02 to $45.25.
Overall, the healthcare sector slumped 3.4 percent.
Materials, a sector that includes gold producers and other resource-based companies, was the lone gainer among the index's 10 main sectors, rising 0.7 percent.
The Canadian dollar was trading at 78.64 cents U.S., down from an average price of 78.71 cents United States on Wednesday. Heating oil fell 1 cent to $1.63 a gallon. On the Nasdaq, 2,303 issues fell and 567 advanced. Silver gained 14 cents to $16.39 an ounce.
US crude oil tumbled 2% to $48.59/bbl, failing to hold above $50 as a report from OPEC showed crude production among the group's members rose in July.
Ongoing global glut concerns lingered in oil markets despite a bigger-than-expected draw in USA crude inventories. The euro slid to $1.1752 from $1.1793.
Sterling was last trading at $1.3009, up 0.27 percent on the day. MSCI's broadest index of Asia-Pacific shares outside Japan closed 0.13 percent higher, while Japan's Nikkei .N225 lost 0.30 percent. South Korea's Kospi fell 0.2 percent.
Notable: Odubel Herrera hit his 35 double of the season in the first inning for his 50th extra-base hit this season. Hansel Robles (7-3) got the final two outs in the eighth and AJ Ramos finished for his 22nd save in 24 chances.
Jammu: An army jawan was killed as Pakistani troops resorted to unprovoked firing on Indian posts along the line of control ( LoC ) in Krishna Ghati sector in Poonch district of Jammu and Kashmir Saturday evening, a defence spokesman said.
A following bus was forced to swerve out of the way, narrowly avoiding the 33-year-old woman as she fell backwards into its path. Police said the man was arrested at a property in the Chelsea area, taken to a south London station and later released.
" Hopefully, next season I'll be here, and now we're not going to spend how we have spent this season I assure you that ". He added: "We played four games, one with four at the back and the last three with three at the back".
On Wednesday, Mr Trump followed up his "fire and fury" warning with a boast about USA nuclear capabilities. Nothing says "vacation" like the threat of nuclear annihilation, at least according to President Trump.
In Services sector, Liberty Global plc ( LBTYA ) holds floating shares of 959.64 million and 959.64 million outstanding shares. News stories about Liberty Global PLC (NASDAQ:LBTYK) have been trending somewhat positive this week, Accern Sentiment reports.
Wenger also stated that lack of focus on the part of his defenders cost Arsenal the first two goals they conceded. Asked about Arsenal's title chances, Wenger said: "There are six or seven teams who can win the league.
Earlier on Thursday, North Korea revealed a plan to launch ballistic missiles toward a major US military hub in the Pacific. ET (1434 GMT), the Toronto Stock Exchange's S&P/TSX composite index fell 70.95 points, or 0.47 percent, to 15,146.38.
North Korea responded by claiming it is preparing a plan to fire missiles at the USA territory of Guam in the western Pacific. " President Trump's threat to rain down "fire and fury" on North Korea is like pouring gasoline on a fire", Humphrey wrote.
Five attempts to stop PDP convention failed - Makarfi
The delegates agreed that the crises in the states should be resolved within the period but prior to the congresses. Thank you distinguished party men and women, ladies and gentle men for your time and attention.
LG reportedly working on V30 Plus smartphone
Samsung is expected to take the wraps off its Galaxy Note 8 smartphone on August 23 at the company's "Unpacked" event. When Apple and Samsung add "Plus" to the name of the smartphone , they mean that the version of the device is larger.