New Zealand's asking the US whether imposing 10 percent tariffs is fair.

President Donald Trump announced mass tariffs last week - triggering market chaos and retaliatory action from China, which now faces 104 percent levies. 

Trump's billionaire sidekick, Elon Musk, today labelled a White House trade adviser a 'moron' for the economic implications.

Prime Minister Chris Luxon says our economy needs certainty.

He explained he doesn't think the 10 percent tariff is appropriate, and the case will continue to be made to US officials.

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