Donald Trump’s controversial proposal to give a $5,000 “dividend” to all US adults if Republicans maintain control of Congress in November’s elections would not be paid out from US tax revenues, according to the US commerce secretary, Howard Lutnick.

“It’s not tax money,” Lutnick said in an interview with NBC News, adding that the administration could “earn the money that Donald Trump wants to pay out, not from the deficit and not from taxpayers”.

In a speech at the Republican midterm convention rally in Dallas, Texas, on Wednesday, Trump said he would issue the dividends “because of our tremendous strength and success economically” and likened the payment to a one-time, tax-free $1,776 “Warrior Dividend” approved for about 1.45 million US military service members last year.

Trump suggested the dividend, which could cost as much as $1tn if paid out to all Americans, could come in part from tariff revenue.

“If the Republicans win, you win with us, and you get $5,000,” he said, adding that it would be called “the Trump dividend”.

But the proposal has been widely criticized, in part because the US national debt recently surpassed $40tn, up from $10tn in 2008, marking a near 300% increase over 18 years.

Lutnick told NBC that some of the dividend money could come from a planned commerce department program to charge wealthy visitors to the US to pay up to $5m to extend their visas.

“We have a waitlist of more than 100,000 people who want to come,” he said, and calculated that this could raise $500bn. He also cited the government’s $8.9bn investment in chipmaker Intel, which has since appreciated in market value, from $20 per share to $100.

In his comments, Lutnick joined with other administration officials in floating ideas on where the $5,000 checks might come from.

Kevin Hassett, director of the National Economic Council, told Bloomberg TV that the White House is considering a “reconciliation process” in Congress to fund the program.

“We can do it in a fiscally responsible way,” Hassett said. “The bottom line is there are multiple paths to getting it done – don’t underestimate President Trump.”

JD Vance has also suggested tariff revenues would cover the cost and that the payments would not go to wealthy Americans.

However, the supreme court has ruled that revenue raised by Trump’s “liberation day” 2025 import tariffs must be returned, and an earlier proposal to return $2,000 to US taxpayers from tariff receipts was more than the revenue that had been raised, according to the nonpartisan Tax Foundation.

Trump’s $5,000 dividend proposal comes as a recent Associated Press poll found that only about three in 10 US adults, or 32%, approve of how the president is handling the economy, down from 40% at the start of his second term.