A Reuters report earlier quoted USA government and private-sector sources as saying China had backtracked on nearly all aspects of a draft trade agreement with the United States.
On Sunday, Trump tweeted he would raise tariffs on $200bn worth of Chinese goods from 10 percent to 25 percent by the end of the week, and would "soon" target the remaining Chinese imports with tariffs, sending stocks and oil prices lower on Monday.
United States officials say they got an inkling of China's second thoughts in talks last week in Beijing, but that the backsliding became even more apparent in exchanges over the weekend.
Bean futures plunged on Monday after the president sent a tweet saying the US would raise tariffs on Chinese goods to 25% from 10% but managed to end up a half cent yesterday. US Trade Representative Robert Lighthizer confirmed on Monday that the duty increases would take effect.
United States officials are insisting that any deal be strictly enforced so that China lives up to its promises - something they say Beijing has repeatedly failed to do in the past.
A spokesperson at the Chinese Embassy in Washington did not immediately respond to queries about the USA assertions.
The trade negotiation team, which has been riven by internal divisions over China hardliners and more pro-trade voices in the past, is consciously seeking to put on a more united front as the talks reach their end stages, an official said.
Speaking to reporters, White House spokeswoman Sarah Sanders separately said the Trump administration has received an "indication" that China wants an agreement. China's Ministry of Commerce said vice premier Liu He should be expected in Washington on Thursday. Both Mnuchin and Lighthizer considered that unacceptable, given China's history of failing to fulfil reform pledges. -China trade dispute, to the talks.
"China reneged on a dozen things, if not more".
Trump announced the increase in a Twitter message on Sunday.
The US, which accuses China of unfair trading practices, launched a trade war against China a year ago.
Chinese stocks have now fallen around 6% so far this week. Should Trum;p carry through with his threats, stock markets could plunge and markets world wide could react negatively. Trump told a rally with supporters in Florida.
On Wednesday morning, USA stock market indexes were mostly weaker again, pointing to a third straight day of losses on Wall Street.
In the USA the S&P 500 fell for the fourth session in five days, declining by as much as 2.1%. "They're competing with our companies", said Scott.
Chinese officials have said talks are ongoing and that the changes it made were part of "the process of negotiation", according to Reuters. The official disputed the assertion that China was backtracking on its promises, adding that USA demands were becoming more "harsh" and the path to a deal more "narrow" as the negotiations drag on.
Top Chinese negotiator Vice Premier Liu He heads to Washington this week for talks, and some investors have seen Trump's threat as a negotiating tactic.
While these numbers sound massive, it's important to consider that the USA gross domestic product is now running close to $21 trillion on an annualized basis.
To avert escalation, some of the sources said, Liu would have to scrap China's proposed text changes and agree to make new laws. Investors who have been around for decades also understand that big corrections occur from time to time in the middle of great bull markets, often for reasons that may sound bleak in the middle of any given day but are forgotten within a week or month.
"The Trump administration seems to have concluded that it is time to get it done. But for now ... come Friday there will be tariffs in place", he added.