The Dow Jones Industrial Average lost 29.75 points, or 0.13 per cent, to 22,329.48 on Friday. The S&P 500 erased 1.61 points, or 0.06 per cent, to 2,498.99, Xinhua news agency reported.
The Nasdaq Composite Index was down 8.31 points, or 0.13 per cent, to 6,414.38.
Tensions between the two countries escalated as North Korea said on Thursday that it may consider testing a hydrogen bomb in the Pacific Ocean. If successfully conducted, the test would be the Asian country's first nuclear test beyond its borders.
North Korean top leader Kim Jong Un on Friday responded to US President Donald Trump's threat this week to "totally destroy" North Korea, saying Trump "will face results beyond his expectation".
Analysts said investors became uneasy amid the tensions and were seeking safe-haven assets before the weekend.
Meanwhile, Wall Street was still digesting the latest Federal Reserve decision.
The US central bank on Wednesday kept interest rates unchanged, but announced that it will start to unwind its $4.5 trillion balance sheet from October, a further step to end the loose monetary policy.
It was widely expected that the Fed may raise rates by the end of December.
(This story has not been edited by Social News XYZ staff and is auto-generated from a syndicated feed.)
About VDC
Doraiah Chowdary Vundavally is a Software engineer at VTech . He is the news editor of SocialNews.XYZ and Freelance writer-contributes Telugu and English Columns on Films, Politics, and Gossips. He is the primary contributor for South Cinema Section of SocialNews.XYZ. His mission is to help to develop SocialNews.XYZ into a News website that has no bias or judgement towards any.