At its worst, the FTSE 100 was down 121 points, or 1.6%, at around 3pm, also pressured by some companies going ex-dividend, and disappointing export and construction data. There was renewed nervousness in France after a auto rammed a group of soldiers in a suspected terrorist attack.
Gold enjoyed another strong session as traders sought out safe havens, with the price lifting 0.1% to 1,287.8 U.S. dollars an ounce.
"When President Trump declared that the United States is "locked and loaded should North Korea act unwisely", investors became even more fearful".
European stocks also fell sharply Friday, leaving the Stoxx Europe 600 with its worst weekly decline since November, just before the US presidential election was held.
"We're through most of the earnings season and the valuations [in the stock market] become a bit problematic when you have something like North Korea come up", said Maris Ogg, president at Tower Bridge Advisors, as quoted by CNBC. He said Thursday that his first threat to unleash "fire and fury" may not have been tough enough.
On that note, the Global Times also pointed out that: "if the US and South Korea carry out strikes and try to overthrow the North Korean regime and change the political pattern on the peninsula, China will prevent them from doing so". It began to rise sharply this week. On an IFRS basis profits before tax surged from £534m in the year-ago period to £940m, for earnings per share of 10.6p, with the latter up by 33%.
The group said it will pay £24 million for the stake in the firm, which will consist of 25 existing Domino's stores in the capital. Davis arrives having spent the previous three years in the same position for fellow FTSE 250-listed firm Greene King.
Anglo-South African financial services company Old Mutual was down 1.2 percent on Friday despite announcing that it intends to list two divisions in 2018.