An image of Harriet Tubman seen on a $20 bill. (H.G. Smith / Ohio History Connection / MGN)

An image of Harriet Tubman seen on a $20 bill. (H.G. Smith / Ohio History Connection / MGN)

*A Republican congressman has launched an effort to block the Treasury from redesigning U.S. currency, a move that could prevent the government from replacing Andrew Jackson on the front of the $20 bill with abolitionist Harriet Tubman.

Rep. Steve King of Iowa has offered an amendment to a spending bill barring the use of funds to redesign any Federal Reserve note or coin, reports The AP.

Tubman would become the first African-American on U.S. paper currency and the first woman on paper currency in a century.

King has yet to state why he opposes the redesign.

His amendment would also keep Susan B. Anthony off the back of the $10, even though Alexander Hamilton’s portrait will remain on the front; and a number of changes to the back of the $5, including images of Dr. Martin Luther King and Marian Anderson.