US President Joe Biden visited Philadelphia on Sunday to remember the memory of assassinated civil rights pioneer Martin Luther King Jr., as he continues to push for voting rights legislation and coordinated action to tackle increasing extremism.

Biden’s trip to the “City of Brotherly Love” comes just hours after an FBI hostage rescue team raided a synagogue in Colleyville, Texas, freeing three hostages following a 10-hour siege. Earlier, another captive had been released.

The president, who was updated on the incident as it unfolded, said there was still more to learn about the hostage-motivations, taker’s but vowed to “fight against anti-Semitism and the development of extremism in this nation.”

To commemorate Monday’s Martin Luther King Jr. Day, Biden and first wife Jill Biden are assisting at Philabundance, a food relief charity in Philadelphia.

In a proclamation issued on Friday, Biden warned against complacency and emphasized the need of continuing King’s work by implementing laws to safeguard voting rights, resisting the development of white supremacism and other kinds of extremism, and advocating for more economic fairness.

“Living up to his legacy, and what Dr. King hoped our Nation might become, necessitates more than meditation; it necessitates action,” Biden said in the proclamation.

“That is why Congress must approve Federal law to defend the right to vote, which is under threat from a nefarious mix of voter suppression and election tampering. We must tackle the plague of racism and white supremacy, which is a stain on our country, and ensure that hatred has no safe haven in America.”

However, Biden’s efforts to pass voting rights legislation appear doomed after Democratic Senators Kyrsten Sinema and Joe Manchin stated their opposition to changing the Senate’s filibuster rule, which requires 60 of the 100 senators to agree on most legislation in a chamber where Democrats now hold only 50 seats.

Senate Majority Leader Chuck Schumer has stated that discussion on the voting rights legislation would resume on Tuesday. If Republicans obstruct the bill as expected, Schumer indicated he is still willing to seek a change in the Senate’s filibuster rule in order to get it passed. However, given Sinema and Manchin’s positions, efforts to amend the filibuster look dead.

Biden told reporters on Thursday that he wasn’t sure the law could pass right now, but he pledged to keep trying.

“One thing is certain: like every previous significant civil rights law that has passed, if we fail the first time, we may try again. We squandered this opportunity.”

On Thursday, the Democratic-controlled House of Representatives enacted a voting measure. But Democrats cannot overcome universal Republican opposition in the Senate without changing the filibuster.