Japan's Nikkei ends marginally lower

Japanese markets fluctuated before ending on a flat note after a powerful 8.7 magnitude earthquake struck off Russia's Kamchatka Peninsula, triggering a tsunami that sent waves crashing into coastal areas and prompting alerts across the Pacific.

The Nikkei average finished marginally lower at 40,654.70 ahead of the Bank of Japan's interest-rate decision on Thursday, with no change in interest rates expected. The broader Topix index settled 0.40 percent higher at 2,920.18.

ANA Holdings tumbled 4.1 percent and Advantest dropped 1.1 percent after announcing their earnings results while Sumitomo Pharma surged 16.3 percent after a rating upgrade by JPMorgan.