Morning Bid: Yen sinks as BOJ holds - and it's the KOSPI's best day

A look at the day ahead in European and global markets from Gregor Stuart Hunter

What a wild ride. Markets in Asia staged a blistering rally on Friday after the scorching selloff in tech stocks earlier this week, while the yen resumed its descent as the Bank of Japan left interest rates on hold.

South Korea's KOSPI blasted as much as 17% higher, alongside gains of more than 7% in Taiwan and a jump of more than 5% in Japan's Nikkei 225 as traders pounced on battered chipmaker shares. MSCI's broadest index of Asia-Pacific shares outside Japan was up 4.7%.

Despite Friday's record gains, the KOSPI was still on track to lose almost 25% in July, marking its largest monthly loss since the Asian financial crisis in 1997.

Currency markets, meanwhile, were processing the implications of unprecedented coordinated intervention by Japanese and Korean foreign exchange authorities on Thursday to strengthen their respective currencies against the U.S. dollar. For Tokyo, it was the latest in a string of market forays by authorities this year to halt the yen's decline, but it was a rare move by Seoul.

The intervention boost didn't last long for the yen, which fell on Friday to 160.69 after the Bank of Japan's rate-setting committee kept rates on hold, in line with market expectations. The won also reversed some gains after reaching its strongest level in nine months overnight.

Stocks took their cues from Wall Street's gains on Thursday, with S&P 500 e-mini futures up 0.3% in Asian trade after strong earnings from Amazon and Sony during the Tokyo trading session, though Apple forecast revenue growth below analysts' estimates as it struggled with chipmaking bottlenecks.

Korean chipmaking heavyweights Samsung Electronics and SK Hynix, followed suit, soaring nearly 30% on Friday.

In early European trades, pan-region futures were up 0.6%, German DAX futures gained 0.4%, and FTSE futures were 0.4% higher.

Key developments that could influence markets on Friday:

• Company earnings: ExxonMobil, AbbVie, Chevron, ITV, NatWest, Puma, Taylor Wimpey

• Economic events:

• UK: Nationwide house prices for July

• France: Preliminary CPI for July, producer prices for June

• Germany: Unemployment for July

• Euro Zone: CPI, HICP Flash for July

• Debt auctions: UK: 1-month, 3-month and 6-month government debt

(Reporting by Gregor Stuart Hunter; Editing by Sonali Paul)