European stocks fell sharply across the board Wednesday as investors around the world piled cash into safe-haven assets amid increasingly dangerous rhetoric between North Korea and the United States.

The region-wide Stoxx Europe 600 index, the broadest measure of share prices, was marked 0.4% lower at 381.07, extending its three-month decline to around 3.7%. The SMI benchmark in Zurich was the biggest decliner in the region, falling 1.3% in the opening hour of trading as investors sought safety in the Swiss franc, which rose 1.12% against the euro and pushed the value of stocks which earn the bulk of their revenues in U.S. dollars lower.

Britain's FTSE 100 was marked 0.45% lower at 7,506 points, although gold mining companies Fresnillo Plc (FNLPF) and Randgold Resources (GOLD - Get Report) posted solid 2.2% gains amid a $7 per ounce jump in bullion prices as investors moved money into safe-haven assets. Markets around the region, including Germany's DAX performance index and the CAC-40 in Paris, fell more than 0.8% in the first hour of trading.

The U.S. dollar, which gained against both the euro and the pound in overnight Asia trading, trimmed its advance as investors moved into gold, the franc, U.S. Treasury bonds and the yen amid threats of an attack on the U.S. territory of Guam by North Korea after President Donald Trump told reporters Tuesday that "North Korea best not make any more threats to the United States" and that any aggression from Pyongyang would be met by "fire and fury like the world has never seen".

Officials in North Korea said they were "carefully examining" a strike on Guam, which is home to around 163,000 people and two U.S. military installations and threatened a further "all-out war wiping out all the strongholds of enemies, including the U.S. mainland" in a government statement.

President Trump promises "fire and fury" for North Korea.
President Trump promises "fire and fury" for North Korea.

The yen's gains helped push the Nikkei 225 in Tokyo down 1.3% to close at 19,738.1 points while the broader MSCI Asia ex-Japan index was marked 0.57% by 09:00 London time. The European single currency traded as low as 1.1719 overnight, a level it hasn't seen since July 28, before paring loses to around 1.1740 in early regional trading.

Gold prices gained around $7 per ounce, taking the price of the bullion for immediately delivery to $1,267 per ounce in early London trading while benchmark 10-year Treasury bond yields, which move in the opposite direction of prices, fell 2 basis points to 2.25%.

Early indications from U.S. equity futures suggest a second session of declines on Wall Street after each of the three major indices fell sharply into the close of trading Tuesday after Trump addressed the North Korea with reporters at his golf resort in Bedminster, New Jersey.

The Dow Jones Industrial Average is priced for a 35-point pullback from its Tuesday close of 20,085.34 points while the Nasdaq is set up for a 30-point, or 0.44%, decline at the opening bell. The broader S&P 500 looks ready to fall 7.75 points, or 0.31%, at the start of trading.

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