*

Trump says U.S. "may" or "may not" join Israeli bombing of

Iran

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Oil hovers near 4-1/2-month peak on risks of supply shock

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Dollar firm on haven demand despite mixed signals from Fed

*

Super-long JGB yields up, medium-term yields slip after

issuance

report

(Updates to afternoon Asia trading)

By Kevin Buckland and Johann M Cherian

TOKYO, June 19 (Reuters) - Global stocks edged lower on

Thursday while investors took cover in safe havens such as gold

and the U.S. dollar gained as financial markets were on edge

over the possible entry of the United States into the week-old

Israel-Iran air war.

President Donald Trump kept the world guessing about whether

the United States will join Israel's bombardment of Iranian

nuclear sites, telling reporters outside the White House on

Thursday, "I may do it. I may not do it."

The Wall Street Journal said Trump had told senior aides he

approved attack plans on Iran but was holding off on giving the

final order to see if Tehran would abandon its nuclear

programme.

Europe's main equities index pointed to a lower open

, while Germany's DAX futures were down 0.3% in

Asia afternoon hours.

U.S. S&P 500 futures slipped 0.1%, although most

U.S. markets - including Wall Street and the Treasury market -

are closed on Thursday for a national holiday.

"Market participants remain edgy and uncertain," said Kyle

Rodda, senior financial markets analyst at Capital.com.

"Speculation remains rife - fed probably strategically by

the Trump administration - that the U.S. will intervene,

something that would mark a material escalation and could invite

direct retaliation against the U.S. by Iran," he said. "Such a

scenario would raise the risk of a greater regional conflict,

with implications for global energy supply and probably economic

growth."

Much of the recent nervousness in markets has been centred

around crude supply shocks from the Middle East which were

reflected in elevated crude prices. Brent crude edged

down to $76.6 per barrel on the day, but remained not far from

the 4-1/2-month peak of $78.50 reached on Friday.

The gloomy mood hampered Asian stocks, with Taiwan's stock

benchmark down 1.5%, and Hong Kong's Hang Seng

sliding 2%.

Prices of traditional safe-haven assets such as gold

edged higher by 0.1% to $3,372.36 per ounce, while the U.S.

dollar firmed against the euro, the Australian

and New Zealand dollars.

CENTRAL BANK POLICY

Overnight, the Federal Reserve delivered some mixed signals

to markets. Much to Trump's displeasure, policymakers held rates

steady as expected and retained projections for two

quarter-point rate cuts this year.

However, Fed Chair Jerome Powell struck a cautious note

about further easing ahead, saying at his press conference later

that he expects "meaningful" inflation ahead as a result of

Trump's aggressive trade tariffs.

Strategists at MUFG said the Fed "is underestimating the

weakness in the economy that was present before the tariff

shock, specifically, almost ignoring the cracks that have been

visible in the labor market for years."

"We maintain our view that the longer they wait to ease, the

more they may need to do."

Markets will now look to a string of central bank policy

decisions out of Europe for any possible catalysts.

In Britain, despite Wednesday's report showing inflation

cooled as expected last month, the Bank of England is widely

expected to keep interest rates steady as policymakers consider

the potential energy price shock from the Israel-Iran conflict.

Sterling was flat at $1.34 ahead of the decision.

Central banks in Switzerland and Norway are both also

anticipated to deliver policy decisions later in the day.

In Japan, longer-dated Japanese government bond yields

rose, while medium-term yields

declined after Reuters reported

that the government intends to cut sales of super-long bonds by

about 10% from the original plan.