FRANKFURT, Germany (AP) Doubts over whether Wall Street can keep on posting record gains weighed on global stock markets Tuesday.

Investors remained cautious a day after the Dow broke 16,000 and the S&P breached the 1,800 mark both were firsts. Stocks in Europe and Asia eased following a late retreat Monday in New York.

The Dow Jones industrial average has surged 900 points since early October and Wall Street has not suffered a significant pullback in the past two years even though the U.S. economic recovery has been painfully slow.

Comments from influential investor Carl Icahn also reinforced jitters that stock prices are out of step with reality.

"Nothing he said was particularly surprising as a lot of people have been thinking the same thing about these moves higher, but it did prompt some profit taking above the psychologically important 1,800 level on the S&P, and 16,000 on the Dow," Michael Hewson, a senior analyst at CMC Markets said.

In Europe, Britain's FTSE 100 fell 0.6 percent to 6683.14 and France's CAC 40 lost 1.0 percent to 4277.12 . Germany's DAX was off 0.5 percent at 9,181.06 after hitting a record high Monday. A stronger than expected reading for the German ZEW index of optimism among investment analysts was not enough to push shares into positive territory.

Futures pointed to a retreat on Wall Street, with Dow and S&P 500 futures both down 0.1 percent.

Earlier in Asia, Japan's Nikkei 225 stock average closed down 0.3 percent at 15,126.56 and China's Shanghai Composite Index dropped 0.2 percent to 2,193.13. Australia's S&P/ASX 200 lost 0.6 percent to 5,352.90. Hong Kong's Hang Seng was little changed at 23,657.81 while Seoul's Kospi rose 1 percent to 2,031.64.

Stocks around the world had been buoyant over the past few trading sessions, largely in the slipstream of developments on Wall Street. The catalyst was Janet Yellen, who is slated to become the next Fed chairman. She expressed strong support for the Fed's low interest-rate and bond buying policies aimed at stimulating U.S. growth. Near-zero rates on fixed-income investments have pushed investors into riskier but potentially higher yielding assets such as stocks.

Markets, however, remain on edge for signs the central bank will start reducing its purchases of government bonds and mortgage securities totaling $85 billion a month.

Elsewhere, trading was fairly muted. Among currencies the euro was down modestly at $1.3502 while the dollar was more or less unchanged at 99.87 yen. And in the oil markets, a barrel of benchmark New York crude fell 15 cents to $92.88 a barrel.