The Senate blocked a proposal targeting transgender athletes from women’s sports during its weekend debate on a sweeping voting bill, with Republicans and Democrats signaling that the broader legislation’s path through Congress remained uncertain.

Saturday’s action took place during a rare weekend session in Washington, where senators discussed the voting legislation that would set new requirements for voter registration and add a photo ID requirement at the polls, the Associated Press reported. The legislation is backed by Republican President Donald Trump, who has pressed Congress to move on the package and to add priorities to it.

The amendment at the center of Saturday’s vote would have penalized educational institutions that receive federal funding if they allowed individuals “assigned male at birth” to participate in women’s sports. Senators rejected the amendment by a 49-41 margin, a result that drew a clear line around Trump’s sports-related priority in the debate.

The broader voting bill under consideration is the Safeguard American Voter Eligibility Act, also known as the SAVE America Act or the SAVE Act. The House passed the measure earlier in the year, but Trump has said he wants additional items added as Congress debates the package.

Trump has also urged Congress to block sex reassignment surgeries on some minors as part of the debate, and it was unclear whether the Senate would vote on that request. In addition, Trump has said he wants the House-passed bill to include a ban on most mail-in balloting, an idea his allies have framed within a wider push he has made for years against mail ballots.

Republicans focused in particular on voter ID requirements as the Senate debated how the bill would work in practice. Senate Majority Leader John Thune said Saturday that “Republicans haven’t made any final decisions about how to conclude this,” adding that the Senate was trying to have a “fulsome debate” and to put lawmakers “one way or the other” on the record.

Sen. John Husted, a former Secretary of State in Ohio, argued there were “no good excuses” not to require photo identification at polling places, saying “This works. It’s being implemented all over the country.” The proposal would require photo IDs at the polls and could override many forms of ID that states currently allow, including fishing and hunting licenses or college IDs, and it would also require people voting by mail to include a photocopy of their ID with their ballot.

Democrats countered that the bill’s approach would restrict access. Senate Minority Leader Chuck Schumer said the new requirements would be “a bureaucratic nightmare,” arguing that Republicans want to end vote by mail and also would block online registration and registration through some institutions such as college campuses and churches, as well as registration at the DMV. Democrats also said the bill would allow the Department of Homeland Security to review state voter rolls in a way they believe could lead to voters being purged.

While the Senate was taking up the voting bill in detail, the timing for any end to the floor debate was unclear as senators prepared to leave town at the end of the next week for a two-week spring recess. Thune said on Saturday that “at some point that’s a that’s a possibility” for when Republicans might start moving to end debate, but senators—including Sen. John Kennedy of Louisiana—said they did not know when that end point would come.

In the near term, the debate’s likely outcome remained tied to Senate rules. Republicans hold 53 seats and have said repeatedly that they do not have enough support to move the bill past a legislative filibuster threshold or to find another workaround, with Democrats expected to block the broader legislation after the extended debate.