In an apparent response to Trump's tweet, a statement issued by North Korea's official KCNA news agency claimed the president is "driving the situation on the Korean peninsula to the brink of a nuclear war".
Such tensions remained high, with North Korea's state media saying on Thursday that North Korea will develop a plan by mid-August to launch intermediate-range missiles at the US territory of Guam.
The Swiss and the yen are often sought in times of geopolitical tension partly because both countries have big current account surpluses.
The Swiss franc, the other traditional safety-play among currencies, has benefited too.
The euro edged down 0.2 percent to $1.1726.
ENERGY: Benchmark U.S. crude gained 28 cents to $49.84 a barrel in electronic trading on the New York Mercantile Exchange.
"If the USA and South Korea carry out strikes and try to overthrow the North Korean regime and change the political pattern of the Korean Peninsula, China will prevent them from doing so", the editorial's authors said.
Peers Aviva and Prudential also closed down 2.1% and 2.3%, respectively, with financial services suffering amid the tensions between the USA and North Korea.
The franc wasn't the only beneficiary to the risk-off sentiment sweeping markets. The insurer said its interim profit jumped on the back of an increase in operating profit, supported by strong growth in its retirement division, but warned that it expects "some adverse experience to continue emerging albeit at a reduced level" in the second half of 2017.More news: 'Mass casualty situation' reported at New Hampshire hospital
The euro was 0.14 per cent higher against the United States dollar.
"While the two nations are at loggerheads, it is going to be hard to imagine money flowing into stocks", said David Madden, market analyst at CMC Markets UK.
Overall, the FTSE 100 was down 0.8% in afternoon European trade, pulled lower by G4S. "Pretty remarkable, perhaps even extraordinary, considering", said Tim Ash, strategist at fund manager BlueBay. Hong Kong's Hang Seng was off 0.3 percent.
The Japanese Yen has sharply appreciated against its major trading partners, following the escalation in geopolitical tensions between the United States and North Korea. It should be kept in mind that the inflation figures have the ability to impact the prospects of higher U.S. interest rates, and this will possibly have a direct correlation to the value of Gold. It is heading for a 2.5 percent drop for the week.
Crude futures meanwhile extended losses on fears of slowing demand and lingering concerns over global oversupply.
US crude was down 0.9 percent at $48.16 per barrel, on track for a weekly loss of 2.9 percent.
Possibly due to the lack of appetite for risk in the market, the euro suffered on Thursday, down slightly against the dollar by 0.09% at 1.1749, slipping towards a two week low. The pan-European STOXX 600 hit its lowest level since the end of March, down 1.1%.