President Donald Trump’s proposal to send $5,000 to every American adult if his Republican Party maintains control of the House and Senate in the November election needs congressional approval, House Speaker Mike Johnson said Sunday, while pledging to try to make it happen.

Trump made the unusual pitch at the party’s midterm convention in Dallas last week, promising a “Trump Dividend” if voters keep the GOP in power on Capitol Hill. The president later told CBS News Texas that he did not think Congress would need to authorize the payments, though he did not specify how he could spend more than $1 trillion without lawmakers’ authorization.

But Johnson, R-La., said congressional approval is needed. “I would assume, yes, he’d need Congress to act, and that’s a creative idea,” he said.

A few hours later, Trump said he would deliver on his promise. “The 5,000’s going to happen, 100%,” he told reporters before boarding Air Force One in Ireland, where he attended a pro golf tournament at his resort.

Johnson, meanwhile, said he would work to get Trump’s proposal through Congress despite a small Republican margin.

“He’s the big ideas president. We’re going to try to implement everything we can,” he said. “I commit that Congress will work through it and find consensus on that like they have to do everything else.”

The dubious election-year gambit could cost more than $1 trillion, putting further strains on the country’s nearly $1.8 trillion annual budget deficit and exacerbating concerns of inflation. The economy is confronted by persistent inflation and increasing interest rates, a tough combination for governing Republicans as they seek to hold on to control of Congress.

The president argues that payments would be possible because of the strong economy, but consumer sentiment is weak as gasoline prices rise because of the war with Iran and wages struggle to keep pace with inflation.