Trump said it was "highly unlikely" he would accept China's request to hold off on the increase.
The comments ran counter to recent speculation about a possible deal when Trump meets with Chinese President Xi Jinping at the G20 summit in Buenos Aires later this week.
"Trump's pessimistic view on the chances of a game-changing China trade deal may puncture global equity markets' optimistic start to the week," said Sean Callow, a senior FX analyst at Westpac in Sydney. "Combined with last week's harsh report from the U.S. trade representative, investors have only the flimsiest hope that the Trump-Xi meeting in Argentina will amount to more than a hill of soybeans."
The early reaction was limited to a drop in trade-sensitive currencies, including the Australian dollar, with share markets yet to open in Asia.
The U.S. dollar remained firm for the moment at 113.60 yen , while the euro nursed losses at $1.1328. That left the dollar a shade firmer at 97.089 against a basket of currencies.
Shares in Apple Inc fell after-hours in reaction to Trump's comments that tariffs could also be placed on laptops and iPhones imported from China.
Trump's remarks came just as the mood among investors had shown signs of brightening. Wall Street took heart from an upbeat holiday shopping period.
European stocks also bounced on Monday, on talk that Italy was preparing to rework spending plans that have fuelled tensions with the European Union, though coalition leaders later said the government was sticking to its main 2019 budget goals as it awaits a full cost analysis of its most important spending measures for next year. Even oil managed to regain a little ground after the gut-wrenching slide of recent weeks.
The rally came after the S&P 500 on Friday recorded its lowest close in six months, down more than 10 percent from September's peaks, putting it in "correction" territory.
In commodity markets, oil prices climbed nearly 3 percent on Monday in what was seen as largely a technical correction after weeks of losses.
Brent crude futures rose $1.68 to $60.48 a barrel, while U.S. crude gained $1.16 to $51.58 a barrel.
(Reporting by Wayne Cole Editing by Leslie Adler)
(This story has not been edited by Devdiscourse staff and is auto-generated from a syndicated feed.)