The yen is often sought in times of geopolitical tension, partly because Japan has a big current account surplus, and it being the world's biggest creditor nation, there is an assumption Japanese investors may repatriate their foreign holdings in times of heightened global uncertainty.
The local currency closed at 1,142.00 won against the United States dollar, down 6.80 won from the previous session's close.
Australian shares were down 1.5 percent, set for a weekly loss of 0.8 percent.
According to reports, North Korea said it was completing plans to fire four intermediate-range missiles over Japan to land near the U.S. Pacific island territory of Guam. The S&P hasn't moved more than 0.5 percent in one day since July and has fallen more than 1 percent only twice this year. "We have no choice but to acknowledge the risks, and to report that financial markets are reacting to them".
Overnight North Korea dismissed as a "load of nonsense" warnings by U.S. President Donald Trump that it would face "fire and fury" if it threatened the United States. "It shouldn't surprise that it's going to rally a little bit on this increased tension", said Bechtel.
Trump took specific aim at North Korean leader Kim Jong Un, saying, he had "disrespected our country greatly", and would not be "getting away with it". The stock fell $166 to $1,882.94.
The benchmark S&P 500 index tumbled more than 1 percent on Thursday, only the third time this year it has fallen that much, while the Nasdaq shed more than 2 percent. The market is concerned that North Korea could strike before any preemptive attack by the U.S.
The medium-term outlook depends on the BoE - Governor Carney and company is expected to find it hard to hike policy rate given the downside risks to growth. But it fell Wednesday and Thursday-its first consecutive down days in a month-and ended morning trading Friday down 1.9%.
It had retreated to trade nearly flat on the day at 109.17 yen per dollar by 0711 GMT but was still 0.2 percent stronger against the euro at 128.28 yen.
Commenting on the impact of the political sabre-rattling, Old Mutual Global Investors' Ned Naylor Leyland, responsible for gold and silver investing, said any further escalation could serve to drive the metals' price even further. The September copper contract was down two cents to US$2.91 a pound. They were at 2.201 percent early on Friday.
The dollar eased slightly against a basket of major currencies .DXY to 93.356.
The Canadian dollar edged down 0.20 cents to 78.73 US cents, while oil prices gained 39 cents to 49.56 USA dollars a barrel and gold prices increased 19.10 to 1,281.70 USA dollars an ounce.
About 6.48 billion shares changed hands on US exchanges on Wednesday compared with the 6.16 billion average for the last 20 sessions.
Crude oil prices fell on Thursday, on concerns of lingering global oversupply as Russian Federation considered a future output resumption and OPEC boosted its July production numbers. Dillard's slumped 15.3 percent after the chain booked a loss for the second quarter as increased inventory led to big discounts.
In central bank news, the Reserve Bank of New Zealand held steady on interest rates at 1.75 percent on Thursday. It is poised to end the week down 1 percent.