"As Vice President, Joe Biden was a close friend of New Zealand and visited here in 2016, the most senior US politician to do so since President Bill Clinton attended APEC in 1999.
"New Zealand will continue to work side-by-side with the United States on the issues that matter to both of us, including the prosperity, security, and sustainability in the Indo-Pacific and Pacific Island regions.
"The campaign by the President-elect has also shown the shared interests we have in addressing global challenges like Covid-19 and climate change.
"There are many challenges in front of the international community right now, the message of unity from Joe Biden positions us well to take those challenges on."
The Prime Minister also acknowledged outgoing President Donald Trump.
"New Zealand has enjoyed positive and cooperative relations with the United States over the period of the Trump Administration, especially in the Indo-Pacific and Pacific Island regions," Ardern said.
She has joined British Prime Minister Boris Johnson, French President Emmanuel Macron, Canadian Prime Minister Justin Trudeau and other world leaders in offering her congratulations.
Although US President Donald Trump isn't conceding defeat, people in other parts of the world have started celebrating Biden's election victory and have expressed hope for what will follow.
CNN's Van Jones delivered a teary celebration.
"Welcome back America !" tweeted the mayor of Paris.
Paris Mayor Anne Hidalgo called Biden's victory "a beautiful symbol to act more than ever together against the climate emergency", referencing the Paris climate accord that Trump pulled out of in 2017.
New Zealand Green Party co-leader James Shaw also echoed that sentiment yesterday.
Word of the victory in Pennsylvania that pushed Barack Obama's former vice president past the threshold of 270 Electoral College votes needed to take over the Oval Office brought widespread relief in world capitals.
In Rome, people gathered in a coffee bar broke out in cheers when media outlets delivered the news.
A city official in Berlin said: "After the birth of my son, the election of Joe Biden is by far the best news of this year."
"Everything won't get better overnight, but Trump is finally gone!" tweeted the official, Sawsan Chebli.
Western allies paid scant heed to Trump's claims that the divisive race wasn't over, instead quickly looking forward to a fresh start with a new administration in Washington.
"We're looking forward to working with the next US government," German Foreign Minister Heiko Maas tweeted.
"We want to work in our cooperation for a new trans-Atlantic beginning, a New Deal."
Italy's foreign minister, Luigi Di Maio, closed his tweeted message of congratulations with Italian and US flags: "Ready to keep on working to make our relations ever stronger in defence of peace and freedom," he said.
Former President and close friend of Biden, Barack Obama has also sent his congratulations to the winning pair on Twitter.
The election of Kamala Harris as the first Black woman Vice President also struck an immediate chord internationally.
"It makes us proud that the first woman to serve as vice president of the USA traces her roots to India," said the leader of India's opposition Congress party, Rahul Gandhi. Harris' late mother was from India. Kamala is Sanskrit for "lotus flower", and Harris gave nods to her Indian heritage throughout the campaign.
"She will be an incredible example and important role model for young girls throughout the world, showing them girls and boys enjoy the same rights and opportunities," Belgian prime minister Alexander De Croo said.
- With AP
