Top US trade officials said China had backtracked on previous commitments made in talks, and this reversal was what prompted President Donald Trump's earlier announcement that the United States would raise tariffs on billions of dollars worth of Chinese goods on Friday.
"Over the course of the last week, we have seen an erosion in commitments from China," US Trade Representative Robert Lighthizer said at a press briefing on Monday.
He added that the Chinese delegation would still be coming to Washington for trade talks, which will now begin tomorrow, a day later than previously scheduled.
But unless there is an agreement by Friday, the entire US trade team is unified in recommending to Mr Trump that the US go ahead with tariffs, said Treasury Secretary Steven Mnuchin, who was at the briefing.
Mr Trump announced on Twitter on Sunday that US tariffs of 10 per cent on US$200 billion (S$272 billion) worth of Chinese goods will be raised to 25 per cent. He also threatened further tariffs on almost all other untaxed Chinese goods.
He had postponed the hike, originally scheduled for March, citing good progress in talks at the time.
Sunday's announcement took observers by surprise and sent markets into a tailspin, but the comments by Mr Lighthizer and Mr Mnuchin showed the impending tariffs as less an impulsive move by Mr Trump and more fuelled by frustrations arising from the deeper disagreements between Beijing and Washington.
The latest impasse lowers the chances that the trade war can be resolved in this round of talks, dashing the hopes of White House officials and trade watchers that a deal could be reached by the weekend.
Mr Mnuchin said that the deal had been 90 per cent done and that negotiators had been in the process of planning a summit between Mr Trump and Chinese President Xi Jinping. But over the weekend, China moved away from language in the agreement that would have changed it substantially, he added.
Mr Lighthizer, without giving details on specifically what promises China had broken, said: "We're moving backwards instead of forwards and, in the President's view, that's not acceptable."
Mr Trump's tough stance on China has won plaudits from both the American left and the right, but the rare bipartisan support also makes it politically difficult for him to accept any watered-down deal.
Republican Senator Marco Rubio wrote on Twitter on Monday that he was unsurprised that China was trying to go back on changes they had previously agreed to.
"For years, they have had counterparts so desperate for a deal they allowed them to get away with this," he said in a swipe at previous Democrat administrations, adding that Mr Trump was "the first to ever pose a credible threat to walk away from a bad deal".
Mr Trump's former chief strategist Steve Bannon, a China hawk, similarly urged him not to soften his stance against China, in a commentary published on Monday by The Washington Post.
"(The) President's best political option is not to surrender, but rather, to double down on the tariffs - they have been highly effective in pressuring the Chinese without harming the US economy," he wrote.