Ted Cruz reversed course Thursday night and stopped blocking a bipartisan aid package to help communities like Flint, Mich., replace aging lead pipes that have contaminated their water supplies.

Earlier Thursday, aides to the Texas senator running for president confirmed that Cruz was holding up the legislation because he wasn’t ready to vote on the package for the time being.

“Our staff is reviewing the bill,” said Cruz spokesman Phil Novack.

A few hours later, right before the Republican presidential debate was set to start in Houston, Cruz decided to allow the bill to advance. “Cruz has reviewed the bill now and will not prevent it from moving forward,” Novack said.

Before that decision, aides would not say what specific issues Cruz had with the legislation. The Texas senator is not the only senator who has not yet signed off on the measure and several GOP aides said the issue could be quickly resolved. But the Senate will now not be able to move ahead on the aid package until at least next week.

A bipartisan group of ten senators, led by Michigan Democrats Debbie Stabenow and Gary Peters, announced Wednesday that they had reached a deal on several funding options for cities struggling with water contamination.  The package includes $70 million in credit subsidies for water infrastructure projects that could be used to replace the corroded pipes that continue to leech lead into the drinking water in Flint.

It also includes $100 million in subsidized loans and grants to help states with tainted water and $50 million for public health programs.

The funding package was introduced as an amendment to a major energy bill sponsored by Energy and Natural Resources Chairwoman Sen. Lisa Murkowski (R-Alaska). Republican leaders in the Senate moved to speed up consideration of the bill earlier this week, but they need all 100 senators to agree on which amendments they are willing to consider to put the legislation on a fast track.

Cruz was the most prominent holdout.

Cruz’s objections came to light after  Sen. Charles E. Schumer (D-N.Y.) vice chairman of the Senate Democratic Conference, told reporters Thursday that Democrats were ready to vote on the funding package but a Republican was standing in the way.

“It’s a presidential candidate,” Schumer said. “I’m not to name names.”

The energy bill has had a rocky path in recent weeks. Democrats blocked the bill earlier this month over a dispute concerning how much aid should be provided to Flint. Now they’re on board, but the bill is not guaranteed a smooth path in the House, according to several aides.

The aid package could still survive even if the energy bill fails. The bipartisan group that drafted the aid package also made sure it could be considered as an amendment to a different Flint aid bill that passed the House earlier this month.