Global stock markets on Monday failed to recoup last week's losses, as traders warily eyed geopolitical uncertainty.
Wall Street equities treaded water while markets in Europe and Japan slid, suffering from lingering concern over President Donald Trump's volatile administration and unclear prospects for achieving economic reform.
Worries over Trump's stalled economic agenda and upcoming high-stakes Washington fights had hurt global stocks on Friday, with valuations pressured further by the terror attacks in Spain as investors sought haven investments such as the yen and gold.
Markets appeared to be hoping for hints from central bank chiefs later this week.
"Global sentiment remains jittery on exacerbated US political uncertainty and geopolitical concerns, while the Fed's key Jackson Hole symposium looms on the week's horizon," commented Schwab analysts.
The cautious mood on markets comes as investors look to a central bankers' gathering in Jackson Hole, Wyoming on Friday for hints about a future with less monetary stimulus on both sides of the Atlantic.
"Traders are keen to get more insight into the plans of the two central banks" direct from Federal Reserve chief Janet Yellen and European Central Bank President Mario Draghi, Oanda analyst Craig Erlam pointed out.
The Fed is expected to announce next month that it will wind down its nearly-$4.5-trillion balance sheet.
And ECB policymakers appear set to unveil in autumn a long-awaited "tapering" or gradual reduction of its tens of billions in monthly bond purchases.
Meanwhile, major takeover activity within the oil and car sectors failed to lift overall sentiment.
European markets were little moved by French oil giant Total's announcement that it would buy Maersk Oil, a unit of the Danish shipping giant A.P. Moller-Maersk, for $7.45 billion (6.35 billion euros).
Total shares gained 0.3 percent, although in Copenhagen A.P. Moller-Maersk shares won 2.9 percent in late trading.
Total said the deal would make it the second-largest operator in the North Sea, with substantial operations in Britain, Norway and Denmark.
Elsewhere Monday, China's Great Wall Motor signalled an intention to make an ambitious offer to buy all or part of Italian-American car maker Fiat Chrysler Automobiles.
FCA shares jumped 6.9 percent in Milan. US-listed FCA shares rose 7.0 percent.
Sempra Energy rose 1.6 percent after it reached a deal to acquire Oncor, a Texas energy distributor, for $9.45 billion in cash and $9 billion in assumed debt, topping a bid by Warren Buffett's Berkshire Hathaway.
Asian traders moved cautiously Monday following fresh turmoil in the White House, with Tokyo ending down 0.4 percent.
- Key figures around 2040 GMT -
New York - Dow: UP 0.1 percent at 21,703.75 (close)
New York - S&P 500: UP 0.1 percent at 2,428.37 (close)
New York - Nasdaq: DOWN 0.1 percent at 6,213.13 (close)
London - FTSE 100: DOWN 0.1 percent at 7,318.88 points (close)
Frankfurt - DAX 30: DOWN 0.8 percent at 12,065.99 (close)
Paris - CAC 40: DOWN 0.5 percent at 5,087.59 (close)
EURO STOXX 50: DOWN 0.7 percent at 3,421.72
Tokyo - Nikkei 225: DOWN 0.4 percent at 19,393.13 (close)
Hong Kong - Hang Seng: UP 0.4 percent at 27,154.68 (close)
Shanghai - Composite: UP 0.6 percent at 3,286.91 (close)
Euro/dollar: UP at $1.1810 from $1.1762 at 2100 GMT
Pound/dollar: UP at $1.2895 from $1.2885
Dollar/yen: DOWN at 109.00 yen from 109.22 yen
Oil - Brent North Sea: DOWN $1.06 at $51.66 per barrel
Oil - West Texas Intermediate: DOWN $1.14 at $47.37 per barrel