Talks have stalled on President Biden’s infrastructure bill that he and Senate Majority leader Chuck Schumer had both been eager to pass prior to Congress’ August recess.

The bill, which is set to include $600 billion in new spending for things such as broadband, water funding, highways and transit, has seen issues arise over how to pay for those components, as well as how much to spend, especially when it comes to transit and a prevailing wage requirement, both of which are major sticking points for Democrats, The Associated Press reports.

Democrats have insisted on a transit funding increase to expand the public transit system, with the idea that it would help contribute to fighting climate change, as well as there being a prevailing wage requirement for both existing public works programs and new ones. With Republicans in disagreement over some of these points, it has led to a roadblock that creates issues over the looming planned August recess.

However, some are still optimistic a deal can be passed prior to that, with Sen. Rob Portman, R-Ohio, expressing that he thinks things are going in the right direction.

“I just spent all day talking to Democrats and Republicans, all my colleagues, and we’re making progress,” he told reporters.

Schumer also said he was “fully committed to getting the bill passed, and warned that an agreement not being reached could lead to cuts on the upcoming recess.

“The bipartisan group of senators has had nearly five weeks of negotiations since they first announced an agreement with President Biden. It’s time for everyone to get to yes and produce an outcome,” Schumer said on Monday.

GOP sources have also stated that the negotiations have continued to stall because Schumer and Biden were trying to “reopen numerous issues the bipartisan group had already agreed to,” and urged both sides to try and be more flexible.

The legislation passing is crucial for the Biden administration, as the package was one of the key promises he made to get the U.S. economy back on track. It is set to be followed by a $3.5 trillion reconciliation package that plans to expand Medicare benefits, fund more healthcare, childcare and education initiatives and combat climate change.

While Senators remain stalled on the negotiations, an Associated Press poll has found that 8 in 10 Americans favor an increase in infrastructure spending.