Christopher Luxon has no concerns about Joe Biden's ability to lead US if re-elected

Christopher Luxon says he has no concerns about US President Joe Biden's ability to lead, should he be re-elected.

There have been growing calls for the 81-year-old Democrat to stand aside and let someone else take on Donald Trump this November, following a shambolic debate performance last month.

Biden himself called it a "bad episode", and has signalled his intention to run again, claiming he is the most qualified to beat Trump, the presumptive Republican nominee and convicted fraudster.

The prime minister has been in the US capital, Washington DC, meeting other world leaders both in and out of the NATO alliance, which is grappling with the ongoing Ukraine dilemma - how to support a close friend and fellow democracy, without escalating Russia's war beyond its borders.

Luxon told media on Friday morning (NZ time) he has had a couple of "lovely" but informal interactions with Biden, praising his "great sense of humour".

As for Biden's ability to serve a second term as president if re-elected, Luxon said he "really enjoyed" his interactions with the 81-year-old.

"We were able to talk about issues across the Indo-Pacific and the Pacific Islands in particular… my interactions were very positive and very engaging."

This week one of the Democratic Party's biggest fundraisers, Hollywood star George Clooney, called on Biden to drop out, saying he was clearly not the same candidate that ran just four years ago.

Asked directly if Biden was "sharp", Luxon said "yes, absolutely".

"Off the interactions I had, they were excellent interactions. He was on top of his brief, we had a positive interaction. [His potential in ability to serve] was not a consideration that I had."

Luxon will soon meet with California Governor Gavin Newsom, who has been tipped as a potential replacement for Biden as the Democrats' candidate for president.

Luxon said the US political system is "very large" with "many layers", and it was important that he had relationships "across the whole of the system".

"California is the fifth-biggest economy in the world, and there's a huge opportunity for us to collaborate more, particularly around climate and also around renewable energy but also in the technology spaces as well."

Luxon said New Zealand was open to doing more for the war-battered nation, talking up his "good affinity" with Ukrainian President Volodymyr Zelensky. New Zealand's aid so far has topped more than $130 million.

"He knows to ask for things if he needs things. We will continue to spend more money… Ukraine must win this war. It is non-negotiable. It has to be done. Absolutely more money on direct military aid, more money on humanitarian assistance, we've put more money into the drone programme… they're actually fighting for democracy, and that's something we believe in."

Luxon said as a small country New Zealand did not have the budgets of larger countries, but it was important to make a contribution.

"We live in a very lovely part of the world… when you're in a different part of the world, democracy gets real, real fast and you don't take it for granted …

"We need to stand up for this international rules-based system that has actually served New Zealand so incredibly well and served the world so incredibly well since World War II. And we have benefited tremendously from that, but it's under threat."

He said that mattered even more to small countries.

"It's moved from 'rules' to 'power', and that's not good for small countries."

Luxon chaired a meeting of the 'IP4' countries - Australia, Japan, the Republic of Korea and New Zealand - who are friends with NATO, but not formal members of the alliance.

"IP4 leaders discussed the way North Korea's ballistic missiles and weapons are now being used by Russia to fight its war in Ukraine. Moscow and Pyongyang's behaviour is escalating tensions in Europe and here in the Indo-Pacific," he said in a statement following the press conference with media.

The IP4 nations condemned North Korea, as well as having talks with Zelensky on the situation in Ukraine.

New Zealand not joining NATO

Luxon said there was no talk of New Zealand formally joining NATO, which currently has 32 members - all of them in the northern hemisphere. New Zealand is currently a 'global partner' of the alliance, formed after World War II.

"That's not something that would happen. But what we're indicating with the IP-4 [is that] we have potential flashpoints - a Ukraine could happen in East Asia."

Particular flashpoints could be North Korea, parts of the disputed South China Sea or Taiwan, among others.

"A Ukraine could happen in our region, and that's why what happens… in Europe and across the Atlantic actually has an impact in the Indo-Pacific, and vice versa."

Pacific engagement

Luxon also had a "pull-aside" with Biden and United States Secretary of State Antony Blinken on US engagement with the Pacific region.

"That's been good, because we want like-minded countries standing up for these values across the region… it was a very good meeting."

Luxon said he agreed with comments from the head of NATO that defence spending needed to be at least 2 percent of GDP, and New Zealand would increase its own once its new military leadership had put together a review of its capabilities and a new long-term strategy.

Luxon said Zelensky did not invite him to Ukraine during their most recent meetings, but an invite was open and he would be happy to go if it showed support for Ukraine.

"The message very clearly is that we cannot lose that war in Ukraine. We cannot have Russia get away with invading a sovereign nation-state - and that matters much to me and to New Zealand, because we are a small country and we rely on those international rules of law and we respect sovereign nation-states…

"We cannot have Ukraine lose this war. That is unacceptable."

Sports junkets a low priority

As for future international trips, Luxon said voters should not expect to see him at sporting events. He said he will likely not be going to Spain for the America's Cup later this year because he has to "fix the country".

"The last thing the New Zealand people need to see is me at the Olympics or me at the America's Cup."

He said Team New Zealand were aware of his position.

"I go somewhere where I can do business and I can actually build the relationships that actually are in New Zealand's national interests… I won't be there."