New York - Global stocks were pressured on Tuesday by nagging doubts about US tax reform and worries about a petroleum glut.
Equity markets fell in New York, Paris and Frankfurt and treaded water in London and Tokyo.
Analysts fear the weakness of recent days could hearken a deeper pullback after a series of stock market records over the last month.
There are signs "that markets are starting to look a little overextended," Oanda analyst Craig Erlam said.
Following a relatively uninterrupted rally in equity markets over the last couple of months, many market observers now are beginning to "question whether a correction of some kind is both warranted and healthy," Erlam said.
"Despite another strong earnings season, the rally has stalled which suggest we may now be a levels again that investors can't justify going far above, which may leave them susceptible to a pull back, even one that isn't particularly large," he said.
Meanwhile, analysts said key differences between the tax bills proposed by the US House and Senate could drag out the long-anticipated proposal, a key aspect of President Donald Trump's economic growth agenda.
There have been worries in particular over a Senate provision that would put off promised steep corporate tax cuts for a year.
Investor conviction is being "stymied by festering US tax reform skepticism," according to a market note from Charles Schwab.
Analysts also said lacklustre Chinese economic data and a bearish oil report from the International Energy Agency weighed on sentiment.
The IEA warned that crude markets were expected to be oversupplied in the current quarter and going into 2018. That sent shares of Apache, Halliburton and Schlumberger down around three percent or more.
Bourses in Frankfurt and Paris declined after the euro rallied following stronger-than-expected German growth data.
But London managed to hold steady, propped up by bright news from supermarket giant Tesco, which gained 5.3% after winning approval from British competition regulators for its 3.7-billion takeover of wholesaler Booker and mobile phone titan Vodafone, which jumped 5.1%after swinging to a profit for the first half of its fiscal year after reporting a big loss in the year-ago period.
Back in the US, General Electric continued to sink after new chief executive John Flannery's turnaround plan, unveiled on Monday, disappointed investors.
Shares dropped another 5.9% after losing more than 7.0% on Monday.
Toy maker Mattel jumped 5.1% amid reports it was approached by rival Hasbro about a possible takeover. Hasbro shed 0.9%.
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