Questioned by Rep. Ayanna Pressley, D-Mass., Mnuchin said that he is focused on issuing a $20 bill next year with improved security features that would prevent the bill from being reproduced as counterfeit.
But the imagery won't likely be addressed until 2026 and a new bill issued in 2028, Mnuchin told the House Financial Services Committee. The secretary declined to say whether he would support Tubman's image on the bill.
"The ultimate decision on a redesign will most likely be another secretary later down the road," he said.
In 2016, President Barack Obama's Treasury Secretary Jacob Lew announced plans for Tubman to replace former President Andrew Jackson on the $20 bill, as part of an effort to get more women on U.S. currency. The plan was set to go into effect in 2020.
However, the Trump administration has held off on implementing the plan. At a 2016 town hall on NBC's "The Today Show," Trump called the move "pure political correctness" and suggested putting Tubman on the $2 bill.
ABC News' Adia Robinson contributed to this report.