House Speaker Nancy Pelosi on Thursday called on the Trump administration to reverse its decision to delay putting abolitionist and former slave Harriet Tubman on the $20 bill.

“It is an insult to the hopes of millions that the Trump Administration is refusing to honor Harriet Tubman on our $20 bill. This unnecessary decision must be reversed,” the California Democrat tweeted.

It is an insult to the hopes of millions that the Trump Administration is refusing to honor Harriet Tubman on our $20 bill. This unnecessary decision must be reversed. — Nancy Pelosi (@SpeakerPelosi) June 20, 2019

Pelosi's request comes a day after Senate Minority Leader Chuck Schumer sent a letter to the Treasury Department inspector general asking for an investigation into the decision by Secretary Steve Mnuchin to delay the redesign of the $20 bill to feature Tubman until 2028.

“We do not know the real reason for these decisions, but we do know that during his campaign, President Trump referred to efforts to replace President Jackson’s likeness on the front of the $20 note as ‘pure political correctness,’” the New York Democrat wrote in the letter. "Secretary Mnuchin attempted to explain the delay as necessary to accommodate anti-counterfeiting measures, but it is simply not credible that with all the resources and expertise of the U.S. Treasury and Secret Service, a decade or more could be required to produce a new $20 bill.”

Schumer added, “If the Empire State Building could be completed in 13 months almost 100 years ago, the 21st century Treasury Department ought to be able to get this job done in a reasonable period of time.”

A design featuring Tubman has been underway and was expected to be released next year, The New York Times reported last week, citing officials familiar with the process.

In 2016, then-Treasury Secretary Jack Lew announced the Tubman design after a 10-month process in which the Treasury Department sought public input, receiving thousands of responses. The Obama administration scheduled the unveiling for 2020 to coincide with the 100th anniversary of the 19th amendment, which granted women the right to vote.

At a House Financial Services Committee hearing in May, Mnuchin claimed that new security features made the 2020 deadline set by the Obama administration impossible to meet, delaying the unveiling of any new imagery until 2028 — well after Trump leaves office.

“The primary reason we have looked at redesigning the currency is for counterfeiting issues,” Mnuchin said. “Based upon this, the $20 bill will now not come out until 2028. The $10 bill and the $50 bill will come out with new features beforehand.”

Months before he was elected, then-candidate Donald Trump called the decision to replace Andrew Johnson with Tubman on the bill “pure political correctness” and proposed putting her on the $2 bill instead.