Prime Minister Jacinda Ardern on Tuesday slapped down Donald Trump's talk of an out-of-control coronavirus "surge" in New Zealand as "patently wrong".

She expressed dismay after the US president exaggerated the new virus outbreak in New Zealand as a "huge surge" that Americans would do well to avoid.

"Anyone who is following," Ardern said, "will quite easily see that New Zealand's nine cases in a day does not compare to the United States' tens of thousands."

"Obviously, it's patently wrong," she added of Trump's remarks.

New Zealand had been hailed as a global success story after eradicating local transmission of the virus and Ardern was lauded as the "anti-Trump". But the recent discovery of a cluster in Auckland forced the country to impose new curbs.