Prime Minister Jacinda Ardern has some heavyweight backing from a US Chamber of Commerce head in her quest to get the US to join the Trans-Pacific Partnership trade pact.

After meeting Ardern in New York this morning, Myron Brilliant, the executive vice-president of the US Chamber of Commerce, said the US needed to be more involved in the Asia Pacific region and should have joined the trade pact, the CPTPP.

Earlier this week, US President Joe Biden launched the Indo Pacific Economic Framework and Ardern said while it was a good step after a period of low US engagement in the region, it fell short of a trade deal and she still wanted the US to join the CPTPP.

Brilliant said he agreed with her on that.

"We agree. We should be part of a trade pact that the United States helped launch.

"I think it was a huge mistake for the Trump administration to pull out of the CPTPP, I think it's been a mistake for the Biden administration not to look at that as an opportunity."

The US was set to be one of the countries in the TPP under President Barack Obama, but Donald Trump withdrew from it as soon as he was elected in 2017.

Ardern is hoping for a meeting with US President Joe Biden at the White House at the end of her trip, and Brilliant said if that went ahead it should be in the discussion.

Asked how the US should handle China and its role in the same region, he said "well, show up first of all".

"She should definitely be pushing it - she should absolutely be encouraging the President of the United States to recognise what countries like New Zealand and Australia and Singapore and Japan are telling our President, which is that the United States needs to be in the region.

"Its presence needs to be there, not just as a counterweight to China but in terms of advancing our geopolitical strategic interests in the most dynamic and vibrant region in the world," he said.

He said there were political issues in the US relating to free trade, and the Indo Pacific Economic Framework would at least start talks with the countries in the region.

"It's a second child, let's be clear, to the CPTPP but we need to at least advance our presence in the region in a very significant way."

Brilliant said it was good to see Ardern in New York.

"I think the visit is well-timed, I think the messages around trade liberalisation and the important role New Zealand has in the Asia Pacific is very much welcomed by the business community."

Executive vice president of the US Chamber of Commerce, Myron Brilliant. Photo / Claire Trevett.

He said he knew New Zealand well, and would like to see more happen between the two countries, from tourism to digital health and technology.

Brilliant said they had also discussed the relationship with China and how New Zealand managed its relationship with China.

"I understand as all business leaders do, the importance of [the US] relationship with China and getting it right but also the challenges right now that we have to confront in terms of China's own market behaviour and issues on human rights."

After the meeting with the US Chamber of Commerce and investment management company BlackRock, Ardern said it had come as no surprise that the Chamber held that strong view.

"And we will continue to be strong advocates of the US using that [the CPTPP] as their port of call for a meaningful trade option. Obviously that hasn't been on the agenda domestically [in the US]. They have proposed an alternative framework," Ardern said.

"Our mission as a country needs to be to keep our aspirations high, but also work with what's on the table."

She said if she got a meeting with Biden she would say privately what she was saying publicly.