Choosing his words carefully, Mnuchin pointed to a public statement that Liu had made at a conference in China on Monday, when he called for calm negotiations, and said, "We've been communicating through intermediaries back and forth with him."
Mnuchin later added that "there has been communication going on" but would not comment on any phone calls.
Press officers for the Treasury Department and the Office of the US Trade Representative, who usually confirm such calls, did not respond to requests for comment or clarification.
On Tuesday, a spokesman for the Chinese Foreign Ministry, Geng Shuang, said he still knew nothing of the conversations.
"I have not heard of this situation regarding the two calls that the US mentioned in the weekend," he said during a news conference.
Trump has a long history of citing telephone overtures from unnamed callers to buttress an argument or generate a sense of support for something he is trying to accomplish.
When Trump faced criticism for espousing anti-Muslim policies during the 2016 presidential campaign, he said on Fox News that "I get calls from many people thanking me, who are Muslim." As recently as last month, when Trump decided to insert himself in the effort to get the rapper ASAP Rocky released from police custody in Sweden, he said he was responding to calls from African Americans.
"Many, many members of the African American community have called me — friends of mine — and said, 'Could you help?' " he said.
The confusion over the China calls left commentators in the United States and China grasping for answers about whether one side was lying or if something was lost in translation.
Hu Xijin, the editor of China's The Global Times publication, suggested that conversations between low-level officials in both countries were being overblown by Trump.
"Based on what I know, Chinese and US top negotiators didn't hold phone talks in recent days," he said on Twitter. "The two sides have been keeping contact at technical level, it doesn't have significance that President Trump suggested."
Jim Cramer, the CNBC television host, said it did not matter if Trump was being honest about the phone calls because the president suggested he wanted talks with China to continue.
"Everyone is so focused on whether he's lying, they're not even listening to what he's saying," Cramer said. "What he's saying is, 'Hey, I'll deal.' People are so obtuse."
It is possible that Trump was trying to give a lift to markets this week after stocks plunged Friday amid news that China and the United States were both ratcheting up tariffs. The Dow Jones industrial average and the S&P 500 both climbed by more than 1 per cent on Monday, and analysts attributed part of the rise to positive trade comments.
But some analysts said the relatively modest uptick showed that investors were not going to be mollified by Trump's offhand statements given how quickly his views tend to shift.
For instance, Trump said Sunday that he had second thoughts about escalating the trade dispute with China, only to have the White House press secretary release a statement hours later claiming that he had regrets only about not raising tariffs higher.
"It's absurd to think that senior Chinese officials would call, looking to restart high-level talks, just two days after Mr. Trump raised tariffs on Chinese imports yet again, and then expressed regret that he had not raised them further," Ian Shepherdson, the chief economist at Pantheon Macroeconomics, wrote in a note to clients Tuesday.
Henrietta Treyz, the director of economic policy research at Veda Partners, said Tuesday that major investors tuned out Trump's comments about telephone calls because they assumed that the two sides were in continuous dialogue to end the trade war.
They are paying less attention to remarks that lack specificity from US officials, she said, because Trump, Mnuchin and Larry Kudlow, the director of the National Economic Council, have made many comments that turned out not to be true, including China's agreement to buy more farm products.
Mnuchin and Kudlow are "having much less effect on pumping the market as they used to, and Trump as well," Treyz said.
Still, Treyz said that it was impossible for investors to ignore the president and that the volatility of his policy moves was unsettling markets.
"It makes short-term investing a nightmare and long-term investment draining," she said.
The volatility is unlikely to stabilise anytime soon. Trump made clear this week that he views his ability to sow instability as a feature rather than a bug.
"It's the way I negotiate," Trump said at his closing G-7 news conference. "It's done very well for me over the years, and it's doing even better for the country."
Written by: Alan Rappeport
© 2019 THE NEW YORK TIMES
