Sen. Bernie Sanders (I-Vt.) on Wednesday called for President Biden to invoke the 14th Amendment in order to raise the debt ceiling and avoid a default on the nation’s credit as White House and House GOP negotiators race to strike a deal. 

In an Fox News op-ed, Sanders said enacting many of the proposed cuts Republicans passed in their debt limit bill last month — and that are on the table now — would be “a disaster,” just as a default would be.

“In my view, there is only one option. President Joe Biden has the authority and the responsibility under the 14th Amendment of the Constitution to avoid a default,” Sanders wrote. “This is not a radical idea. Making sure that the United States continues to pay its bills regardless of whether the statutory increase in the debt ceiling is raised or not is an idea that has been supported by Republicans and Democrats.” 

Sanders added that Section 4 of the amendment must be utilized to “continue to pay its bills on-time and without delay, prevent an economic catastrophe, and prevent huge cuts to healthcare, education, childcare, affordable housing, nutrition assistance and the needs of our veterans.” 

“It must be exercised,” he added.

According to Section 4 of the 14th Amendment, known as the public debt clause, the “validity of the public debt” of the U.S. “authorized by law … shall not be questioned.” The section was ratified to ensure the U.S. paid debts incurred during the Civil War.

The White House on Tuesday appeared to rule out invoking the 14th Amendment, though Biden has said in recent weeks he believes he has the authority to do so. However, it would likely get caught up in legal challenges that would stretch past the June 1st “X-date” laid out by Treasury Department Secretary Janet Yellen. 

“The question is could it be done and invoked in time that it would not be appealed as a consequence past the date in question,” Biden said during his trip to Japan last week.

Talks between the White House and House Republicans continue as the two sides try to reach a deal by the end of the week to give all figures involved enough time to pass it before the government defaults.