Ms Ardern has been touring the United States to promote New Zealand tourism and trade, and she met Mr Biden for the first time in person to discuss the Ukraine conflict, gun control, trade, climate change, and the Pacific.
President Biden praised Prime Minister May for her approach to global concerns like as climate change during a 90-minute conversation in the Oval Office at the White House on Wednesday morning (AEST).
“It’s pleasure to see (you) in person, you understand that your leadership has taken on a critical role in this global stage and it really has,” he said.
“Galvanising action on climate change and global economic climate, violence, extremism online like happened at Christchurch call and, you know, I want to work with you on that effort.”
Influence of China in the Indo-Pacific
The President, who recently visited the Quad Leaders' Meeting in Tokyo to discuss China's influence in the Pacific, then told Ms Ardern that New Zealand and the United States needed to work together to stop Beijing from infiltrating the region.
"I want to emphasize that we are not here to dictate or lay down the rules... working together." Mr Biden told Ms Ardern, "We have more work to do in those Pacific Islands."
Prime Minister Anthony Albanese and Foreign Minister Senator Penny Wong attended the meeting to discuss Australia's position.
Ms Wong also visited Fiji last week to meet with leaders, while New Zealand's Foreign Minister Nanaia Mahuta has come under fire from politicians for failing to meet with Pacific leaders in the wake of China's ambitions.
Last week, China launched an eight-nation Pacific visit, during which it was disclosed that island states will be offered policing, security, cyber security, climate change assistance, and a new China-Pacific free-trade deal.
"China's presence in the Pacific is not new; yes, they are working to strengthen their ties, but so should we all... The pace and level of engagement has increased, but it is not new.
"What we're hoping for is that the United States' relationships grow and that they continue to build those constant relationships in our region, because the pace of engagement has accelerated."
The tour was organized after Australia expressed alarm about China's security deal with the Solomon Islands, which could result in a Chinese military installation being built fewer than 2000 kilometers from Cairns.
Guidance on extremist gun violence
After the latest Texas mass killing, Joe Biden sought counsel from Jacinda Ardern, but the White House acknowledged its limitations on gun control in comparison to its close allies.
In a meeting with New Zealand Prime Minister Jacinda Ardern in the Oval Office, Trump mentioned the 51 people killed in mass shootings in Christchurch in 2019. Following the carnage, New Zealand banned military-style rifles and implemented a successful gun buy-back program.
“We need your guidance,” Mr Biden said, referring to the broad US-New Zealand partnership, but particularly on what he called a “global effort to counter violence and extremism online”.
“I want to work with you on that effort,” he said.
Mr. Biden, who paid a visit to the Texas hamlet of Uvalde on Sunday to mourn the deaths of 19 children and two teachers, said there was a "awful lot of pain" and that "most of it is preventable." Mr. Biden had just returned from a visit to the site of another mass shooting in New York state, this time targeting African-Americans.
Mr. Biden favors an assault weapons prohibition, but there are currently insufficient Republicans in the Senate to form a functioning majority. Even his less contentious idea for enhanced background checks on gun buyers could be shot down in the Senate.