Japan's top government spokesman said Wednesday the nation's alliance with the United States remains essential for global peace and stability, regardless of the outcome of the U.S. midterm elections.

Chief Cabinet Secretary Minoru Kihara also said at a press conference in Tokyo that the government will monitor the financial markets "with a high sense of urgency," after media projections showed that Democrats took control of both houses of Congress in Tuesday's elections.

The alliance "remains the cornerstone of Japan's foreign and security policy" and is crucial to "maximizing its national interests" amid an increasingly volatile and uncertain global situation, Kihara said.

With China's military buildup and North Korea's missile and nuclear programs in mind, Prime Minister Sanae Takaichi's government has been seeking closer cooperation with U.S. President Donald Trump's administration to strengthen the alliance's deterrence and response capabilities.

Kihara said financial markets are driven by "various factors" and that the government should refrain from commenting on the potential impact of specific events, including the U.S. midterm elections.

The Nikkei stock index briefly fell more than 4 percent Wednesday after media projections showed Democrats had regained control of the U.S. House of Representatives.

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