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S&P 500 flat in afternoon U.S. trading

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U.S. dollar up against the yen, at 38-year high

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Investors on alert for yen intervention

(Updates to 1 p.m. ET)

By Caroline Valetkevitch

NEW YORK, June 26 (Reuters) - The dollar hit a fresh

38-year high against the yen on Wednesday, with investor

speculation high that authorities in Japan could intervene to

strengthen the Japanese currency, while global stock indexes

were mixed.

Japan's top currency diplomat, Masato Kanda, said

authorities were "seriously concerned and on high alert" about

the yen's rapid decline.

Japan's low-interest-rate regime, compared with that of the

United States, has continued to weigh on the yen.

The latest slide follows the Bank of Japan (BOJ) decision

this month to hold off on reducing bond-buying stimulus until

its July meeting.

The dollar hit its strongest level since December 1986

against the yen, and it was last up 0.6% at 160.66.

"The market seems to be front-running itself with respect to

BOJ policy," said Eugene Epstein, head of structuring for North

America at Moneycorp in New Jersey.

The dollar index, which measures the greenback

against a basket of currencies including the yen and the euro,

gained 0.31% at 106.00, with the euro down 0.25% at

$1.0686.

On Wall Street, the S&P 500 was last little changed while

the Nasdaq was slightly higher, even as shares of artificial

intelligence chip leader Nvidia ( NVDA ) were down 1.6%.

A sell-off in the previous session wiped $430 billion off

Nvidia's ( NVDA ) market value.

Among the gainers, shares of Amazon Inc rose more

than 3%, bringing the company's market value above $2 trillion,

the fifth U.S. corporation to cross that level.

The Dow Jones Industrial Average rose 43.48 points,

or 0.11%, to 39,156.03, the S&P 500 gained 0.30 points,

or 0.01%, to 5,469.71 and the Nasdaq Composite gained

48.90 points, or 0.28%, to 17,766.56.

MSCI's gauge of stocks across the globe fell

0.89 points, or 0.11%, to 802.88.

European shares slipped, with investor focus among other

things on French elections at the weekend. The STOXX 600

index fell 0.56%.

In the United States, President Joe Biden and former

President Donald Trump on Thursday head to the first of two

debates ahead of their rematch this November.

Investors also are looking for clues about the U.S.

inflation picture and how soon the Federal Reserve could begin

to cut interest rates.

Fed officials have urged patience on interest rate cuts. Fed

Governor Michelle Bowman this week reiterated her view that

holding the policy rate steady "for some time" would probably be

enough to bring inflation under control.

Investors await Friday's release of the U.S. personal

consumption expenditures (PCE) price index, the Fed's preferred

inflation measure, with economists polled by Reuters expecting

the annual growth to ease to 2.6% in May.

U.S. Treasury yields rose amid a pick up in inflation in

other countries.

On Wednesday, Australia consumer inflation accelerated to a

six-month high in May.

The yield on benchmark U.S. 10-year notes rose

6.6 basis points to 4.304%, from 4.238% late on Tuesday.

U.S. crude gained 0.49% to $81.23 a barrel and Brent

rose to $85.56 per barrel, up 0.65% on the day.

Spot gold lost 0.78% to $2,300.96 an ounce.

(Additional reporting by Gertrude Chavez-Dreyfuss in New York;

and Samuel Indyk and Ankur Banerjee; Editing by Shri Navaratnam,

Himani Sarkar, Alex Richardson, Gareth Jones and Alexander

Smith)