Leading Japanese shares hit another seven-year high on Wednesday, adding to the big gains made this week.
The Nikkei closed up 0.4% at 17,197.05 on news that Prime Minister Shinzo Abe might call a snap election and postpone plans to increase the sales tax from the current 8% to 10%.
That marked the highest close since October 2007.
Retailers outperformed, on hopes of a potential delay to the hike in sales tax, which could affect revenues.
Shares in J Front Retailing rose 3%, while Takashimaya climbed 2.9%.
The yen, which had fallen to a seven-year low of 116.11 yen to the dollar on Tuesday, strengthened slightly against the US currency to 115.37 yen.
In Hong Kong, the benchmark Hang Seng Index closed up 0.55% at 23,938.18, while the Shanghai Composite in China finished 1% higher at 2,494.48.
In Australia, the benchmark S&P/ASX 200 index fell 1% to a two-week low of 5,463, despite a survey showing that consumer sentiment rose for a second month in November.