New Zealand's Prime Minister Christopher Luxon on Tuesday made his strongest condemnation yet of the Trump tariffs, days after his Australian counterpart, Anthony Albanese said the US move had "no basis in logic" and "not the act of a friend".

Luxon said the tariffs were a shift away from agreed rules and ran the risk of a global trade war, broadcaster RNZ quoted him as saying.

Worldwide tariffs rolled out by the Trump administration last week included a baseline tariff of 10 percent slapped on Australian and New Zealand exports to the United States, sparking strong reactions from countries that included US allies with major trade ties.

Luxon told reporters he and his government would be the "biggest advocates for free trade on the world stage".

"What actually is concerning me is the shift away from agreed rules and the risks of actually backsliding into a global trade war," he said.

"A trade war is, frankly, in nobody's interest. It will slow global growth, it will hurt jobs and it will reduce the amount of money we have in our wallets," Luxon said.

RNZ quoted New Zealand's Finance Minister Nicola Willis as warning that global inflation could rise by as much as 0.5 percent following the Trump move.

There were no plans to change the country's May budget in response to the profound shift in the economic landscape, but Willis has warned of tough times ahead.

New Zealand exporters have been hit modestly by the tariffs, but Asian markets had been significantly impacted, which would inevitably affect demand for New Zealand exports, she said.