The deadline looms over a series of other significant events this week, with markets also awaiting the UK election on Thursday, and US and euro zone central bank meetings
Asian equity markets ticked down on Tuesday, tracking Wall Street losses as investors fretted over a December 15 deadline for the next round of US tariffs on Chinese imports to take effect.
Adding to the market uncertainty were comments from US Agriculture Secretary Sonny Perdue on Monday that while President Donald Trump did not want to implement tariffs, he did want to see "movement" from China.
The deadline looms over a series of other significant events this week, with markets also awaiting the UK election on Thursday, and US and euro zone central bank meetings.
Investors have focused this year on the risks of the UK crashing out of the European Union without a deal and a sharp escalation in trade war tensions, said Frank Benzimra, head of equity strategy at Societe Generale.
"What you have seen since the end of the third quarter and the beginning of the fourth quarter was these two risks were receding ... And now this week you see those two concerns coming back on the market," he said, adding that he expected their impact to be "short-term."
With investors reluctant to make big bets, MSCI's broadest index of Asia-Pacific shares outside Japan was just 0.05% lower, with China's benchmark Shanghai Composite index off 0.3%.
For its part, a Chinese official said on Monday Beijing hopes to make a trade deal with Washington as soon as possible before new US tariffs are due to kick in this weekend.
Adding pressure in China was new data showing that producer prices fell in annual terms for the fifth consecutive month in November while consumer prices spiked as food costs climbed, complicating efforts to boost demand as economic growth slows.
Australian shares were off 0.19%, while Japan's Nikkei was flat.
"The decision whether or not to raise tariffs on December 15 rests with President Trump and he has continued his constructive ambiguity on the issue which is keeping markets guessing," said Tapas Strickland, a director of economics and markets at National Australia Bank.
Tepid trade followed weakness on Wall Street overnight. The Dow Jones Industrial Average fell 0.38% to 27,909.6, the S&P 500 lost 0.32% to 3,135.96 and the Nasdaq Composite dropped 0.4% to 8,621.83.
Investors were also keeping an eye on the US Federal Reserve, which is expected to keep rates unchanged at its two-day policy meeting, which ends Wednesday.
With rates likely to stay put, analysts say investors will be closely watching policymakers' forecasts for future US economic growth.
On Tuesday, the US two-year yield, watched as a sign of market expectations of Fed fund rates, was at 1.6151%, down from its close of 1.627% on Monday.
The 10-year Treasury yield was at 1.8225% from a US close of 1.831% on Monday.
Following the Fed, investors are likely to scrutinize the first policy meeting led by new European Central Bank President Christine Lagarde on Thursday for clues on where she will take the bank.
While expectations of a Conservative Party victory in Thursday's UK election have powered a rally in the pound, options markets indicate worries of a post-election retreat.
"Polls have been wrong before, so a surprise can't be ruled out - that's exactly what happened in the 2017 election," analysts at ANZ said in a morning note.
"But it's not just about Brexit. Fiscal expansion is also on the cards, with ending austerity a major theme of the election irrespective of who wins," they said.
Sterling, which hit its highest level against the dollar since April on Monday at $1.3180, added 0.06% to buy $1.3151.
The dollar rose 0.06% against the yen to 108.62 and the euro was up 0.05% at $1.1068.
The dollar index, which tracks the US currency against a basket of six major rivals, was down 0.03% at 97.610.
Worries over trade continued to push oil prices lower. Data released on Sunday showed that Chinese exports declined for a fourth straight month, underscoring the impact of the trade war between the US and China, which is in its 17th month.
Global benchmark Brent crude fell 0.08% to $64.20 a barrel and US West Texas Intermediate crude dipped 0.05% to $58.99 a barrel.
Gold was down less than 0.1% on the spot market, fetching $1,460.95 per ounce.