WASHINGTON (AP) — The winner of November’s presidential election will face an epic challenge next year with the coming expiration of nearly $4 trillion in tax cuts — an issue that the Biden White House is highlighting in the runup to November.

Lael Brainard, director of the White House National Economic Council, in a speech Friday emphasized the administration’s differences with Republicans over taxes. In her address at the Brookings Institution, Brainard made a case for higher rates on corporations and the ultra-wealthy in order to support the middle class.

“The expiration of Trump’s 2017 tax package next year will put tax fairness front and center,” Brainard said. “The president is honoring his ironclad commitment to not raise taxes on anyone making less than $400,000 and will cut taxes further for workers and families, paid for by asking corporations and those at the top to contribute more.”