By Ayai Tomisawa
TOKYO (Reuters) - Japan's Nikkei share average eased on Wednesday as the strong yen soured investors' mood, while energy shares continued to benefit from higher oil prices.
The Nikkei edged down 0.4 percent to 16,611.45 points by late morning after earlier traversing positive and negative territory.
"The dollar-yen levels determine the Japanese market so people are staying cautious," said Toru Ibayashi, head of CIO Wealth Management at UBS Securities, adding that investors will likely stay on the sidelines for the next week.
"Whether it's Brexit or other events, when the currency market moves sharply, there will be volatility so most people are not taking positions."
The U.S. Federal Reserve will conclude a two-day policy meeting on June 15, followed by a Bank of Japan meeting on June 16. Traders doubt the Fed will hike rates this summer but expectations are growing that the BOJ will ease again this month or next unless the yen somehow stages a reversal.
Britain will vote on whether to remain in the European Union at a referendum on June 23.
The dollar was down 0.5 percent at 106.86 yen, nearing the one-month low of 106.35 touched on Monday.
Resources shares extended their gains from the previous day as oil prices hit 2016 highs on concerns about global supply shortfalls, with Inpex Corp gaining 1.1 percent and Japan Petroleum Exploration Co advancing 1.6 percent.
Exporters were mixed, with Toyota Motor Corp falling 0.5 percent, Canon Inc dropping 0.8 percent while Panasonic Corp rising 1.5 percent.
Chubu Electric Power Co surged 3.6 percent after the Asahi Shimbun reported that the company plans to ask the government for permission to restart its Hamaoka nuclear power plant's No. 5 reactor.
Following the report, Mizuho Securities raised the company's stock rating to 'buy' from 'neutral."
The broader Topix shed 0.5 percent to 1,334.59 and the JPX-Nikkei Index 400 dropped 0.5 percent to 12,022.09.
(Editing by Kim Coghill)
