Trade meeting in China was overshadowed by a Twitter tirade from President Trump

Chinese and US negotiators held their first face-to-face talks on Wednesday since agreeing to a trade war truce last month, but the short meeting in Shanghai was overshadowed by a Twitter tirade from President Donald Trump.

Washington and Beijing have so far hit each other with punitive tariffs covering more than $360 billion in two-way trade in a row centred on demands for China to curb the alleged theft of American technology and provide a level playing field to US companies.

US Trade Representative Robert Lighthizer and Treasury Secretary Steven Mnuchin shook hands and exchanged pleasantries with Vice Premier Liu He Wednesday morning.

The group then went behind closed doors for around four hours in the first face-to-face negotiations since Trump agreed to a truce with his Chinese counterpart Xi Jinping in June following a breakdown a month earlier.

The talks were relatively brief and the group emerged later, a little earlier than expected, for a group photo before the US trade officials left for the airport without speaking to reporters.

Mr Lighthizer and Mr Mnuchin had arrived Tuesday and joined Chinese officials for dinner and informal discussions -- just as Trump took to Twitter to lambast what he said was a lack of willingness by Beijing to broker a fair deal.

The US leader said Beijing was supposed to start buying US agricultural products but they had shown "no signs that they are doing so".

"My team is negotiating with them now, but they always change the deal in the end to their benefit," President Trump wrote on Tuesday.

"That is the problem with China, they just don't come through," he added.

Mr Trump had previously accused China of reneging on its commitments when talks broke down in May, and his tweets sent hopes of reconciliation tumbling.

"Whatever shred of optimism markets had about the ongoing trade negotiations were dealt as a severe blow when President Trump flew off the handle again," said Stephen Innes, managing partner at VM Markets Singapore.

A commentary in the Communist Party mouthpiece People's Daily on Wednesday complained that as the talks started, "the drums of some Americans struck again on the side, disturbing the main melody".

'Very far apart'

At a press briefing in Beijing on Wednesday, a foreign ministry spokeswoman made it clear which side China saw as responsible for the ongoing trade impasse.

"When one is ill it is useless to ask someone else to take the medicine," said Hua Chunying, when asked about the talks wrapping up in Shanghai.

"I believe the US should show more sincerity and good faith when it comes to trade negotiations."

Stephen Kirchner, programme director of the United States Studies Centre at the University of Sydney, told AFP it was clear that the two sides were "very far apart".

"We can infer these talks were very preliminary, aimed at a refresh after the setback in May," he said.

Days before the Shanghai meeting, Trump threatened to pull recognition of China's developing nation status at the World Trade Organization, which Beijing called "arrogance".

Expectations were already low before the talks, and officials on both sides were keeping a low profile throughout their Shanghai trip.

US trade negotiators entered and left their hotel on Shanghai's waterfront through side doors without going through public areas, and did not stop to speak to press or show their faces.

President Trump suggested Tuesday that Beijing was hoping to delay a deal until after the US presidential election in November 2020, saying China wanted to see if a Democratic opponent wins the vote so it could "continue to rip off the USA".

"He (Trump) can't afford politically to step up and say 'I made a great deal with China' when it's not a great deal," said Derek M. Scissors, resident scholar at the American Enterprise Institute.

"So the most likely outcome is we get nothing until the election."