Updates prices throughout

By Tom Wilson and Rocky Swift

LONDON/TOKYO, May 27 (Reuters) - Global shares advanced and oil prices eased on Wednesday as markets looked for signs of whether a shaky truce between the United States and Iran will be extended.

European shares .STOXX gained 0.3%, following advances for Asian markets, including record highs for Japanese and South Korean stocks fuelled by optimism over AI. MSCI's All-Country World Index also added 0.2%.

Iran said on Tuesday U.S. strikes near the contested Strait of Hormuz represented a "gross violation" of a ceasefire in place for nearly seven weeks. The U.S. said its attacks were defensive in nature.

"A deal might not yet be as imminent as hoped over the weekend," Deutsche Bank analysts wrote. "However it seems talks remain on track despite the targeted U.S. strikes."

Overall, sentiment remained vulnerable as talks continued, aiming to reach a lasting halt to the three-month-long conflict that has rocked energy markets. Investors were also watching central banker comments for how the crisis is affecting the outlook for inflation and interest rates.

Earlier, Asia-Pacific shares outside Japan .MIAPJ0000PUS rose for a fifth straight day to an all-time high, adding 1.1%.

Japan's Nikkei .N225 gained 0.5%, trading above the 66,000 mark for the first time. South Korea's KOSPI .KS11 also hit a record high, gaining 3.4% as chipmaker SK Hynix surged beyond $1 trillion in market value for the first time. nL1N42400A

Domestic rival Samsung 005930.KS surpassed the $1 trillion mark for the first time in early May, while U.S.-listed Micron MU.O did so on Tuesday.

The safe-haven dollar held on to gains from the previous session.

U.S. stock futures ESc1 made slim gains.

Meanwhile, U.S. crude CLc1 fell 2% to $92.04 a barrel, and Brent LCOc1 lost 1.5% to $98.07 per barrel, after a nearly 4% surge in the prior session, sparked by the new U.S. strikes.

CURRENCIES

The dollar index =USD, which measures the greenback against a basket of currencies, was little changed at 99.07. It added 0.15% on Tuesday.

The yen hovered at 159.29 per dollar JPY=, near its May low that spurred Japanese currency intervention. nL1N42400Y

Bank of Japan Governor Kazuo Ueda struck a hawkish posture on Wednesday, saying the war-driven oil shock could become persistent in an environment of high-inflation expectations and rising wages. European Central Bank board member Isabel Schnabel a day earlier advocated for an interest rate hike in June even if a U.S.-Iran peace deal is reached.

The euro EUR= rose 0.2% to $1.16.

New Zealand's dollar NZD= jumped 0.7% against the dollar to $0.5878 after the central bank held interest rates steady but said rates would need to move up sooner.

"We have seen a previously dovish central bank, faced with an economy operating with a negative output gap, prepared to hike rates sooner and more aggressively than previously," ING analysts noted.

In bond markets, the yield on benchmark U.S. 10-year notes US10YT=RR fell 1.8 basis points to 4.473%, down for a third day to the lowest since May 14.

On a light day for economic data, markets were looking forward to Thursday's release of the personal consumption expenditures (PCE) index, the measure favoured by the Federal Reserve for setting its 2% annual inflation target.