WASHINGTON -- For weeks, senators have said they are close to a deal on legislation to help Flint, Michigan recover from the poisoning of its water supply, but on Wednesday another lawmaker threw a wrench in the negotiations.

Sen. Bill Nelson (D-Fla.) put a hold on the agreement just as Sen. Debbie Stabenow (D-Mich.) appeared close to putting out a flame with Republican Sen. Mike Lee (R-Utah) over the legislation.

Nelson doesn’t have a problem with the underlying bill, which makes money available to cities like Flint coping with decaying water infrastructure, or with a separate piece of energy legislation tied to the Flint bill. But he is wary of an offshore drilling amendment that Sen. Bill Cassidy (R-La.) wants to attach to the energy bill. The measure would increase revenue sharing for states that allow offshore oil and natural gas drilling in the Gulf of Mexico.

"Sen. Nelson supports the energy bill and the money for Flint but the Republicans insist on an amendment that would start the process of drilling off Florida’s coast," Nelson spokesman Ryan Brown said in an email. "After four decades of protecting Florida’s beaches and military training areas in the Gulf, Sen. Nelson isn’t going to stop now."

While Cassidy's bill doesn't have to do with Florida specifically, and any final drilling decision is up to the federal government, Nelson's spokesman said the senator is concerned that if the amendment passes the, "huge financial incentive" it grants would create "such immense pressure to continuously open up new areas to offshore drilling that it'd only be a matter of time before they'd start looking to open up areas off Florida's coast."

Before Wednesday, Lee was the only remaining senator preventing a vote on the Flint-inspired bill, saying Michigan had the resources it needed and Congress shouldn't get involved in a local water crisis. Lee said the bipartisan effort to craft a response to Flint amounted to "grandstanding."

"It's outrageous to think we're grandstanding," Sen. Gary Peters (D-Mich.) said Tuesday. "We're trying to find a way to provide resources to the people of Flint. The people of Flint have waited too long."

Bloomberg BNA reporter Ari Natter said on Twitter that Stabenow had reached "a conceptual agreement" with Lee. Asked by HuffPost, a spokeswoman for Stabenow would only say that negotiations continue. And no deal had been reached with Lee, according to a spokeswoman for Sen. Jim Inhofe (R-Okla.), who co-authored the Flint bill.

If the entire package is unable to move before the Senate leaves for its spring recess on March 21, senators will probably look for a different pathway to move money for Flint. Inhofe’s spokeswoman noted that the Water Resources Development Act, currently under review by a committee, could be a viable option.

Democrats originally wanted $600 million in direct assistance to Flint, where the water has been tainted by lead since 2014 thanks mainly to the state government's decision not to treat the water to prevent it from corroding the city's lead pipes. The current version of the proposal, the result of a compromise with Republicans, would provide loan credits to any area facing a water crisis, though Flint is the only one that currently meets the standard set by the draft legislation.

Even in small doses, lead can have damaging health effects, including permanent brain damage in small children.