SINGAPORE, June 18 (Reuters) - Japan's Nikkei share

average rose to touch a four-month high on Wednesday, boosted by

a weaker yen, although investors kept a wary eye on the rapidly

escalating conflict between Israel and Iran.

The Nikkei was 0.59% higher at 38,766.01 as of 0226

GMT, having touched 38,786.64, its highest level since February

21. The broader Topix rose 0.4%.

The biggest boost to the Nikkei came from Uniqlo-brand owner

Fast Retailing ( FRCOF ), Switch-maker Nintendo ( NTDOF ) and chip

firm Advantest ( ADTTF ) that were up 1.4%, 6% and 1.1%,

respectively.

The gains in Japanese shares were capped by geopolitical

tensions, with investors increasingly nervous over the

possibility of a more direct U.S. military involvement in the

Middle East.

Reuters reported, citing three U.S. officials, that the U.S.

military is deploying more fighter aircraft to the region and

extending the deployment of other warplanes. U.S. President

Donald Trump called for Iran's "unconditional surrender."

Maki Sawada, an equities strategist at Nomura Securities,

said the market is cautious about developments in the Middle

East, and will be sensitive to any headlines.

"Market caution seemed to have calmed yesterday, but it is

building again. The weaker yen is providing support," Maki said.

The yen hit a one-week low of 145.445 per U.S.

dollar in early trading. A weaker Japanese currency tends to

boost shares of exporters, as it increases the value of overseas

profits in yen terms when firms repatriate the money to Japan.

Markets shrugged off the move by the Bank of Japan on

Tuesday to hold interest rates steady and decelerate the pace of

its balance sheet drawdown next year.

"Japan remains one of our favoured equity markets," said Ben

Powell, Chief APAC Investment Strategist at the BlackRock

Investment Institute. "Ongoing shareholder-friendly reforms to

boost profitability support our tactical overweight on Japanese

stocks. We prefer unhedged equity exposures, given the yen's

tendency to strengthen during periods of market stress."