Japan's key Nikkei index fell over 4% on Monday after former Defense Minister Shigeru Ishiba was elected head of the ruling Liberal Democratic Party.

Ishiba, set to become prime minister on Tuesday, has said he supports the Bank of Japan raising interest rates while investors are also worried he might raise taxes.

Ishiba’s selection Friday came after trading in Tokyo had closed for the day. The 225-issue Nikkei stock average had jumped 2.3% before the final result as traders bet on a victory by Sanae Takaichi, who opposes higher rates.