Nikkei jumps 1.2%
Japan's benchmark Nikkei 225 share index touched a two-week high of 17,854 points on Wednesday, after being shut for a public holiday in the previous session, as dollar-yen broke through the 120 mark.
That pushed exporters' stocks higher, with Honda and Toyota Motor advancing 2.1 and 1.6 percent each. Sony, which announced Tuesday it will allow the movie "The Interview" to open in selected theaters on Christmas Day, charged 4 percent higher.
Gains in index heavyweights also lifted the share index; Uniqlo clothes brand owner Fast Retailing surged nearly 3 percent while Softbank added 0.3 percent.
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Mainland indices lower
On the last trading session before the Christmas holiday, China's Shanghai Composite index lost 1.9 percent to hit a two-week low on Wednesday, adding to a 3 percent plunge in the previous session.
Large cap financial stocks led declines; Bank of Communications and China Construction Bank receded over 5 percent each, while Agricultural Bank of China and Bank of China made losses of 4.5 and 4 percent, respectively.
Brokerages also put up a dismal performance on Wednesday. Citic Securities and Haitong Securities slid nearly 9 percent, respectively.
Media reports of fresh infrastructure projects failed to excite builders as China Railway Group fell 7.5 percent and Anhui Conch traded flat. On Tuesday, China's National Development and Reform Commission (NDRC) approved $4 billion worth of new bridge and road construction projects, state media said. The new investments come on the heels of approvals worth 209 billion yuan announced two days ago.
In Hong Kong, the Hang Seng index finished little changed. Property developer Greentown China outperformed the bourse to elevate 21 percent after it said China Communications Construction Group (CCCG) is buying a 24.29 percent stake in it for $775 million. Shares of the state-owned CCCG fell 5.6 percent in Shanghai and 9 percent in Hong Kong.