Japan's Nikkei average slid more than 2% to snap a nine-day winning streak on Monday, its first trading day of 2014, as foreign hedge funds unwound positions in futures and large-cap stocks such as SoftBank and Fast Retailing.
The Nikkei closed down 2.4% at 15,908.88 after falling as far as 15,864.44, its lowest level since December 25. The Topix dropped 0.8% to 1,292.15.
Trading was active, with 2.93 billion shares changing hands, the highest in three weeks.
Large caps led the declines. SoftBank Corp shed 3.5% and was the most traded stock by turnover. Fast Retailing Co plunged 5.8%.
On December 30, the index closed at a six-year high with a 57% annual gain, its biggest in more than 40 years on the back of aggressive economic stimulus by Prime Minister Shinzo Abe.