Rhetoric on both sides has hardened despite an agreement in June by Presidents Donald Trump and Xi Jinping to revive efforts at ending the costly fight over China's technology ambitions and trade surplus.
Asia markets were mostly down on Monday, with investors cautious ahead of US-China talks in Shanghai this week and amid more civil unrest in Hong Kong.
Two-day discussions begin on Tuesday with a Washington delegation led by White House Trade Representative Robert Lighthizer.
But analysts are pessimistic about a resolution to the year-long trade dispute between the world's top two economies that has seen $360 billion in tariffs imposed on bilateral trade.
"Hoping for the best but preparing for the worst best describes my view," said Vanguard Markets managing partner Stephen Innes.
"We are not overly optimistic about a positive Shanghai surprise."
Hong Kong was among the biggest downward movers on Tuesday with the Hang Seng Index falling 1.2 percent, after a fresh round of violent protests in the financial hub.
Pro-democracy protesters in the financial hub fought a second consecutive day of running battles with police on Sunday evening in a well-heeled residential district, a day after clashes at a banned rally in a town near the border with mainland China.
China's top policy body on Hong Kong affairs was set to hold an extremely rare press briefing on Monday afternoon on the crisis engulfing the financial hub.
The weekend protests were "factoring quite negatively into the overall risk equation, Innes said, with traders concerned that Washington may speak in support of the demonstrators.
"If they do, it would not only throw this week's trade discussion into disarray but could jeopardise bilateral trade negotiations going forward," he added.
Seoul was down 1.9 percent amid an ongoing trade spat with Tokyo, which restricted the export of materials key to South Korean tech firms earlier this month.
Elsewhere the Nikkei was down 0.6 percent at the lunch break while Shanghai was 0.2 percent lower.
Rate cut expectations
Oil benchmarks were slightly down Monday after ending last week higher on strong US growth figures, and amid continuing tensions over Britain's seizure of an Iranian oil tanker earlier this month.
Expectations of a Fed rate cut have been priced into the market and could see downward pressure on the gold price, said OANDA senior market analyst Alfonso Esparza.
"A 25 basis points cut by the Fed following a more cautious approach co uld lead to downward pressure for the yellow metal, with the $1,400 level under threat," he added.