So far on her trip in Vietnam, Prime Minister Jacinda Ardern has been called Jessica Ardern and New Zealand has been confused with Australia – but at least she now knows her Agriculture Minister Damien O’Connor has good bone density.

The business delegation part of Ardern’s three-day visit to Vietnam, started with a demonstration of Fonterra’s bone density testing machine.

The company claims to have tested more than 100,000 Vietnamese – part of its push to encourage the uptake of dairy in Vietnam.

However, Ardern was less than keen to have her own bone density tested – instead leaving the job to O’Connor.

Fonterra’s general manager in Vietnam, Roshan da Silva, started with a slip calling Ardern “Jessica.”

He explained that osteoporosis was a big issue for women in many Asian countries, including Vietnam. He said the company used Malaysian actress Michelle Yeoh to promote its products: “Even at the age of 60, she still does her own stunts.”

When that was pointed out to Ardern, she said she too did her own stunts.

 “But I also have Damien as a stunt double.” She ushered him toward the stations which test density in the feet, saying “I don’t think this should be just about women.”

O’Connor duly did the test and came out with flying colours. “I think the greater threat to my bones is still the motorbike, not bone density.”

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Minister for Trade and Export Growth Damien O'Connor has his bone density tested in Hanoi during the New Zealand Government mission to Vietnam. Photo / Claire Trevett

The delegation travelled to Ho Chi Minh City on Tuesday night for another day of business events, before Ardern goes to Bangkok for the Apec Summit.

However, even as Ardern goes about Vietnam making her post-Covid “New Zealand is open for business” pitch, Covid-19 was circling.

Ardern did a rapid antigen test after news that Cambodian PM Hun Sen had tested positive two days after they met, while he was at the G20 summit.

Ardern tested negative and a spokesman said she would continue to monitor for any symptoms.

Ardern met with Sen while in Cambodia over the weekend for the East Asia Summit.

Ardern is hopeful of a bilateral meeting with China’s President Xi Jinping at Apec.

PM Jacinda Ardern gets a pomelo picked by Vietnam's PM Pham Minh Chinh in Hanoi. Photo / Supplied

The day before, Ardern had had a colourful day meeting the Communist Party leadership of Vietnam - a day that ended being taken on a garden walk at night by Prime Minister Pham Minh Chinh to pick pomelos: one of the fruit Vietnam exports to New Zealand.

Ardern was welcomed to Hanoi with a military parade outside the bright yellow Presidential Palace, as flag-waving people and students lined the streets of her route.

After placing a wreath at the Ho Chi Minh Mausoleum there was a round of meetings: the political prelude to the business delegation events.

PM Jacinda Ardern inspects the guard of honour with Vietnam's PM Pham Minh Chinh in Hanoi. Photo / Pool

After meeting her counterpart, Chinh, Ardern went to the Communist Party headquarters to meet the most powerful man in Vietnam, party General Secretary Nguyen Phu Trong.

She then met President Nguyen Xuan Phuc before moving on to the National Assembly – Vietnam’s parliament – to meet its Chairman, the equivalent of the Speaker.

After her meetings, Ardern said the political meetings were crucial for the trade delegation aspect of the trip because it was the government that controlled issues such as red tape at the borders.

“In these areas, government has quite a big hand.” Ardern has voiced concern about protectionism creeping in because of the economic problems globally, and Chinh seemed receptive to that concern.

After the meeting, Chinh said the two countries should work together to enforce the trade agreements they were part of: the CPTPP, the Asean-Australia-New Zealand agreement, and RCEP.

He also referred to the need to maintain international law – and his concern about the dispute over the South China Sea in particular.

Ardern noted the two countries had their differences. “The way our political systems operate is one of those.”

However, she said Vietnam did believe in values New Zealand also believed in, such as international law.

“They share the same view that when you see a threat to international law or undermining of the UN Charter, that’s a threat to peace and stability. Vietnam has a very clear eye on maintaining peace in our region. They’ve had a fraught, conflict-fuelled history. You can see why their focus would be on avoiding conflict in our region again because they’ve seen it first hand.”

Both Ardern and Chinh had come fresh from the East Asia Summit, where the topic of discussion was conflicts and tension in the region.