U.S. stocks plunged nearly 2 percent or more, with the Dow wiping out gains for the year on escalating tensions between Greece and its creditors.
Oil fell more than $1 Monday as Greece shut its banks and imposed capital controls, causing investors to flee from riskier assets.
Asian equities were sold down on Monday after Greece failed to clinch a deal with its international lenders over the weekend.
US stocks were tipped to open up on Tuesday, suggesting a degree of calm could return to Wall Street even as Greece looks set to default an IMF loan.
U.S. stocks closed mixed on Friday, posting a loss for the week, as investors digested earnings reports and awaited resolution on Greece debt talks.
Gold was little changed on Friday, after falling to a three-week low, on caution ahead of crunch talks on Greece.
Brent pared losses Friday, but remained stuck in tight trading ranges as investors awaited the outcome of Iranian nuclear talks.
The ongoing Greek debt talks left currency markets in tight ranges on Friday.
U.S. Treasurys were subdued on Friday, with prices a smidgen lower as investors eyed developments in Europe, where a crisis in Greece rumbles on.
U.S. stock index futures fell sharply on Monday, tracking European and Asian markets downwards, as the Greek crisis entered a new chapter after the instigation of capital controls.
China's Shanghai Composite index crashed more than 7 percent on Friday, chalking up its worst single-day loss since January 19.
U.S. stocks closed lower, failing to hold initial gains, as lack of resolution between Greece and its creditors weighed on investor sentiment.
European equities closed mixed on Thursday after wobbling in earlier trade, as hopes for a deal between Greece and its creditors seemed to fade.
Mainland shares endured a sharp selloff late Thursday, while other bourses were lackluster after Greek talks hit a stalemate overnight.
U.S. stock markets were expected to open higher on Thursday, unwinding some of the previous day's losses, with focus on the crisis in Greece.
Bonds fell on optimism that Greece would avert a debt default after its creditors presented a final cash-for-reform proposal to euro zone leaders.
Ongoing Greek debt talks sidelined currency investors, demonstrating their unwillingness to take bold positions as deadlines for a deal come and go.
Gold eased for the fifth straight session on Thursday as traders awaited further news on Greece's negotiations with its creditors.
U.S. stock index futures pointed to a positive open for Wall Street, with focus on a slide in Chinese stocks and developments in Greece.
Crude oil slipped for a second straight day, weighed by weaker U.S. refined fuels markets and potential negative impact from Greece's debt crisis.
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