Investor confidence has been knocked this month by a perfect storm of negative issues, only slightly offset by hopes for further central bank easing measures as the global outlook dims.
Comments from Donald Trump throwing next month's planned trade talks into doubt, as well as his decision to unveil more tariffs on Chinese goods, sent equities tumbling last week and analysts at Goldman Sachs have said they do not expect a deal before the 2020 US presidential election.
The Wall Street titan also warned the standoff could hit US growth, while Treasury yields plunged in a sign of growing concerns for the country's economic health.
All three main indexes on Wall Street ended more than one percent lower on Monday, while there were also losses in Europe and gold -- a go-to asset in times of turmoil -- climbed back above $1,500 to sit around six-year highs.
Increasing unrest in Hong Kong was also moving into global investors' view, as protests extend into a third month, with the city's airport -- a major world transport hub -- cancelling all flights in and out on Monday evening as thousands of demonstrators descended.
- 'Worrying development' -
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The protests are raising pressure on Chief Executive Carrie Lam and led Beijing to warn of "terrorism emerging".
Stephen Innes, managing partner at VM Markets, said: "Dropping the 'T' word is particularly disturbing as it does suggest a more aggressive mainland response, which triggered a wave of risk aversion across global markets."
Hong Kong fell more than two percent while Shanghai ended down 0.6 percent.
Tokyo retreated more than one percent as exporters were hit by a rush into the safe-haven yen, Sydney fell 0.3 percent, Seoul dropped 0.9 percent and Singapore dived one percent.
Manila dived almost three percent while there were also losses in Mumbai, Jakarta, Taipei, Bangkok and Wellington.
In early trade London fell 0.1 percent, while Frankfurt and Paris each dipped 0.3 percent.
Michael Hewson, chief market analyst at CMC Markets UK, said that global issues -- from the trade stand-off and Brexit to Hong Kong's unrest and Middle East tensions -- could be containable for markets.
But he added: "Taken together in the round as a cocktail of risks against a backdrop of central banks almost out of ammunition and you have a recipe for a lot of nervous investors".
Emerging market currencies recovered Monday's losses that came on the back of the shock win in an Argentina presidential primary election by populist centre-left candidate Alberto Fernandez over incumbent Mauricio Macri.
The news saw the country's peso dive 30 percent at one point and the stock market lost more than a third of its value.
OANDA Asia-Pacific senior market analyst Jeffrey Halley said that while contagion from Argentina would be limited, "what it does highlight is that economic populism is alive and well in all corners of the globe -- a far more worrying development in the long-term than a US-China trade war."
- Key figures around 0810 GMT -
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Hong Kong - Hang Seng: DOWN 2.1 percent at 25,281.30 (close)
Tokyo - Nikkei 225: DOWN 1.1 percent at 20,455.44 (close)
Shanghai - Composite: DOWN 0.6 percent at 2,797.26 (close)
London - FTSE 100: DOWN 0.1 percent at 7,220.34
Euro/dollar: DOWN at $1.1194 from $1.1217 at 2050 GMT
Pound/dollar: DOWN at $1.2052 from $1.2076
Euro/pound: UP at 92.89 pence from 92.84 pence
Dollar/yen: UP at 105.30 yen from 105.28 yen
West Texas Intermediate: DOWN 28 cents at $54.65 per barrel
Brent North Sea crude: DOWN 34 cents at $58.23 per barrel
New York - Dow: DOWN 1.5 percent at 25,896.44 (close)