Former prime minister Scott Morrison has warned Australians against welcoming a thawing relationship with China before a landmark visit this week.

Foreign Minister Penny Wong and PM Anthony Albanese will travel to Beijing on Saturday for a visit, including the first meeting with Chinese President Xi Jinping on home soil in seven years.

But Morrison said Australia should be wary of the breakthrough three years after Beijing cut off communication with his government.

Behind only his true motivations for secretly assuming cabinet colleagues’ powers, the question of why the relationship with China reached such a low ebb is the enduring mystery of Morrison’s leadership.

In 2014, Xi spoke of the “vast ocean of goodwill” between Australia and China in a speech to a joint sitting of Parliament.

But one particular move by the Morrison government crashed the relationship.

In May 2020 Australia called for an international inquiry into the origins of COVID-19, complete with visits from officials in the manner of United Nations weapons inspectors.

Some experts suggested an allusion to the lead-up to the 2003 invasion of Iraq was provocative at a time when tensions between Beijing and Washington were already high.

China responded by slapping economic sanctions equivalent to nearly $25 billion, or 5.5 per cent of Australian exports, on barley, wine and coal and cutting off official communications.

“It (communication) should never have stopped, and it wasn’t Australia that stopped it,” Morrison said.

“It was China who stopped it because they didn’t like that we stood up to them.”

But why had Australia – and Australia alone – stood up to the country with the world’s largest army and its largest trading partner?

The same question bothered James Robson, the owner of Ross Hill Wines in Orange.

“We don’t understand why the federal government picked a fight with our biggest customer,” he said.

Two years on, an export market that was once worth $1.2 billion is worth less than $10 million after Australian producers were forced to put an estimated glut of 2.8 billion unsold bottles in the cellar.

Despite the cost to exports, Morrison has never clearly explained why Australia stood alone on the COVID issue.

Plagued, a book about Morrison’s leadership during the pandemic, suggests more diplomatically savvy leaders took advantage of him.

At a critical cabinet meeting in April 2020, Morrison laid out his diplomatic strategy on the COVID inquiry, telling colleagues it was time for Australia to “be more strident in its language about China’s conduct”.

But Morrison botched the other key plank of this plan.

The former PM told cabinet colleagues he would solicit international support and contacted dozens of world leaders from Europe to Africa to enlist them to support the inquiry call.

“Yes, of course. I want to know where it came from as much as you,” UK Prime Minister Boris Johnson is recorded as saying emphatically.

Other European leaders were reluctant to support the idea and focused on  mounting domestic death tolls.

“That said, they were all happy if Australia front-ran it,” wrote authors Geoff Chambers and Simon Benson.

Johnson never came good on that promise.

Wong leaves on Saturday after the government secured a diplomatic breakthrough with China’s agreement to move towards unwinding one of the last significant outstanding tariffs on wine.

She said renewed Australian engagement with China would help the two countries navigate their differences but warned that the relationship could not be expected to return to the relative high point seen 20 years ago.

“When we came to government, we said we wanted to bring a greater level of maturity to the relationship, a greater degree of consistency,” she said.

“We made clear we weren’t going to play the domestic politics with it, but we also said we want to stabilise the right relationship and ensure that Australia’s national interests are safeguarded.”