Washington: Shortly before the Australian Securities Exchange tumbled by 6 per cent at the opening bell, US President Donald Trump said it was “so stupid” to question him about the worldwide market rout that has followed his decision to impose tariffs at levels not seen in nearly 100 years.

Asked on board Air Force One whether there was a limit to the market pain he would tolerate, Trump told the reporter: “I think your question is so stupid. I don’t want anything to go down, but sometimes you have to take medicine to fix something.”

Trump said he had spoken to world leaders from Europe and Asia over the weekend and “they’re dying to make a deal”. But he was not interested in doing so unless the United States’ trade deficits with those countries could be closed.

“Just so you understand the power of what I’m doing, every country is calling and being very solicitous of us ... they’re being very nice,” Trump said.

“This is not sustainable. The United States can’t lose $US1.9 trillion ($3.5 trillion) on trade ... the whole thing is crazy, and I got elected on that basis. The American people understand it a lot better than the media.”

In a post on his Truth Social platform, Trump said tariffs were the only way to cure the country’s “massive financial deficits” with China, the European Union and others.

“They are already in effect and a beautiful thing to behold,” he said. “Some day, people will realise that tariffs, for the United States of America, are a very beautiful thing.”

US markets were expected to fall even further when they opened on Monday, with futures down more than 4 per cent on Sunday evening, New York time.