World shares retreat over concerning tech valuations

An index of global equity markets has eased after hitting a record high as concerns about lofty valuations of leading technology companies weigh on markets.

The benchmark S&P 500 on Wall Street and equities in Europe finished lower as investors digested another blowout quarter from chipmaker Nvidia, the world's most valuable company, but worried about its market value even as it forecast that first-quarter revenue would be a whopping $US78 billion.

On Wall Street, technology and communication services were the biggest losers, with Nvidia's shares closing down 5.5 per cent.

The Dow Jones Industrial Average edged higher by 0.03 per cent, the S&P 500 lost 0.53 per cent and the Nasdaq Composite fell 1.2 per cent.

"People are getting concerned about lofty valuations even though when you look at a company like Nvidia, the estimates, cash flow, and everything else are dramatically higher," said Thomas Plumb, chief executive and portfolio manager at Plumb Funds in Madison, Wisconsin.

"But I think the sentiment will eventually match up with the realities."

In Europe, the broad STOXX 600 index edged lower by 0.05 per cent after touching a new record high. MSCI's All Country World Index eased 0.2 per cent after rising to a record high of 1,063.86.

"It's an increasingly cloudy future for AI," said James St Aubin, chief investment officer at Ocean Park Asset Management in Santa Monica, California.

"It's not that AI isn't going to work out. It's about who's going to be the winners? How do these firms keep competitive advantages? There's a lot of upstream and downstream impact that the market is really having trouble sorting out."

Several heavyweight technology companies finished lower on Wall Street. Alphabet declined 1.7 per cent, Apple fell 0.5 per cent, Amazon lost 1.3 per cent and Tesla shed 2.1 per cent.

Salesforce, which reported quarterly revenue higher than analyst estimates after markets closed on Wednesday, rose four per cent.

London Stock Exchange Group's shares jumped nine per cent after it announced a $4.1 billion buyback under pressure from activist investor Elliott Management, which recently built a stake in the data provider.

Investors are eyeing indirect talks between the U.S. and Iran over their long-running nuclear dispute. Oil prices slipped in a volatile session as markets awaited the outcome of the talks.

Brent crude futures fell 0.14 per cent to settle at $70.75 a barrel. US crude futures settled down 0.32 per cent to $66.21.

Treasury bond prices in the US and Europe edged higher on the back of safe-haven bids as investors grew nervous about tensions involving Iran.

Safe-haven gold rose, with spot gold adding 0.29 per cent to $5,185.04 an ounce.

In currency markets, the dollar rose against major currencies, including the euro and Swiss franc.

The euro was down 0.09 per cent at $1.1798 against the US dollar. The dollar was up 0.23 per cent to 0.774 against the Swiss franc.

The Japanese yen rose 0.16 per cent to 156.1 against the greenback days after the government of Prime Minister Sanae Takaichi nominated two pro-stimulus academics to the board of the Bank of Japan.