Liquidity was thin with Japan on holiday, keeping early moves modest. Hong Kong markets could also be disrupted after a super typhoon brushed the city on its way to landfall in China's Guangdong, the country's most populous province.
MSCI's broadest index of Asia-Pacific shares outside Japan dipped 0.26 percent, snapping three straight sessions of gains.
Australian shares eased 0.2 percent, while EMini futures for the S&P 500 were off 0.19 percent. Treasury futures were little changed, as were the major currencies.
U.S. President Donald Trump is likely to announce new tariffs on about $200 billion on Chinese imports as early as Monday, a senior administration official told Reuters.
The tariff level will probably be about 10 percent, the Wall Street Journal reported, below the 25 percent the administration had said it was considering.
The WSJ also reported Beijing may decline to participate in proposed trade talks with the United States later this month if the Trump administration moves forward with the tariffs.
Other officials who advise the country's leaders are suggesting China impose limits on the sale of parts and supplies needed by U.S. businesses, using "export restraints" to threaten their supply chains.
"Further escalation looks very likely in which the rate will likely be raised to 25 percent and more U.S. tariffs threatened, while China may potentially pull out of trade talks entirely and escalate on the new front of outright export restrictions," wrote analysts at JPMorgan.
"This would of course only inflame the situation further."
In currency markets the dollar index <.DXY> was a fraction firmer at 94.940, having bounced from a low of 94.359 at the end of last week.
The euro held at $1.1628 <EUR=EBS> after retreating from a peak of $1.1721 on Friday, which also marks stiff chart resistance. The dollar was idling at 111.95 yen <JPY=> having run into offers around 112.15/20.
In commodity markets, gold was stuck at $1,193.10 an ounce <XAU=> and some way from last week's top at $1,212.65.
Oil prices eased in early trade with Brent off 9 cents at $78.00 a barrel <LCc1>, while U.S. crude fell 17 cents to $68.82 - Reuters