President Joe Biden signed the Social Security Fairness Act into law Sunday afternoon, marking what is expected to be one of the last major pieces of legislation of his presidency.

Prior to signing the bill, Biden touted the importance of Social Security benefits for working class Americans and said he was “proud to have played a small part in this fight and get to sign it.”

“The bill I’m signing today is about a simple proposition: Americans who have worked hard all their lives to earn an honest living should be able to retire with economic security and dignity,” he said.

The act repeals provisions that limit the ability of some retirees who also collect pensions from claiming Social Security benefits. Among those impacted are retirees who at one time worked as firefighters, teachers, postal workers, police officers, or in other public sector jobs. A provision that limits the benefits allotted to those workers’ surviving spouses is also eliminated.

The bill was passed in the Senate in December after passing the House in November with overwhelming bipartisan support.

Ahead of the bill signing on Sunday, a White House official called Biden “the first President in more than twenty years to expand Social Security benefits.”

“The bill he is signing today will expand benefits by hundreds of dollars per month for more than 2.5 million Americans,” the official said.

As Biden looks to shore up his legacy during his final weeks in office, the official also pointed to other moves that Biden has made to strengthen Social Security and other programs as “reckless” Republicans have worked to make cuts.

Lawmakers across party lines have praised the legislation which stands to help millions of Americans.

“I am so thankful that we in the federal government are keeping a promise on earned benefits to return that which is due to the people who have given their lives to serve the public,” Sen. Bill Cassidy, R-La., said after its passage in the Senate last month.

Democratic Sen. Sherrod Brown of Ohio said, “It is a wonderful way to end the year. We’ll be bringing some equity in my state, where 250,000 workers will be helped by this. It really is to me about this canary pin, and about the dignity of work and fighting for workers.”