Senate appropriators said Thursday they are preparing a supplemental package to combat the Zika virus that will be offered alongside an early spending bill on the floor, the first real movement toward providing emergency funding in either chamber after months of negotiations.  

Appropriations Chairman Thad Cochran, R-Miss., said the chairmen and ranking members of the State-Foreign Operations and Labor-HHS-Education subcommittees are working on a package to provide additional resources to health and foreign aid agencies. Appropriators didn’t disclose how much money the package would contain.  

“It’s my expectation that this proposal will be offered to an appropriations measure on the Senate floor in the near future,” Cochran said.  

The package is being written by Republicans Roy Blunt of Missouri and Lindsey Graham of South Carolina and Democrats Patty Murray of Washington and Patrick J. Leahy of Vermont. Blunt, chairman of the Labor-HHS-Education Subcommittee, said the goal is to attach the supplemental package to an appropriations bill that stands a good chance of reaching the president’s desk and being signed into law.  

“I believe we’re closing in on a number that’s the right number,” he said.  

The Obama administration in February requested $1.9 billion in emergency spending to develop vaccines and combat mosquito populations in foreign countries, among other needs. But Republicans in Congress didn’t accept that number, and after weeks of gridlocked negotiations, the administration yielded to Republican demands and repurposed nearly $600 million of money originally intended to combat the Ebola virus toward the Zika response.  

Sen. Bill Nelson, D-Fla., announced on the Senate floor Thursday that he and Minority Leader Harry Reid, D-Nev ., would introduce legislation to fully fund the administration’s $1.9 billion request.  

The Zika virus, which has already reached a majority of U.S. states, is known to cause microcephaly , a condition of babies born with abnormally small heads. Health officials have warned the virus will spread faster as the mosquito population grows in the warmer months.  

“We hope that working with Blunt and Murray, Graham and Leahy, who’ve already been working, that we do have a sense of urgency about developing a supplemental and moving a supplemental,” said Barbara A. Mikulski of Maryland, the ranking Democrat on Senate Appropriations. “At every briefing we’ve had … we find out it is worse than what we thought.”  

Mikulski said appropriators should “pinpoint a vehicle that will occur sooner than later” to carry the Zika legislation.  

“We must act before July 1. I don’t mean start it July 1 – complete it,” she added. “We are in a race against the clock. We are in a race with the mosquitoes, and right now I would say the mosquitoes are winning.”  

House appropriators, initially thought to be leading the efforts to craft a Zika response, have remained gridlocked in a war of words with the White House over the level of information provided by the administration to the committee.  

House Appropriations Chairman Harold Rogers fended off questions Thursday about how much support a Senate supplemental appropriations bill on Zika would get from the House.  

“We don’t know the content of that bill yet so we’ll reserve judgment until we see what it is they are up to,” the Kentucky Republican said.  

House Speaker Paul D. Ryan, R-Wis., at a press conference, declined to rule out the possibility of a supplemental appropriations measure for Zika. “I’m not going to foreclose the Appropriations Committee’s options,” he said, but noted that House Republicans are still waiting on the administration to answer questions about how it would spend the money.  

Even if the Senate forges ahead and is able to pass the Zika aid as part of a regular appropriations bill, the legislation could run into trouble on the other side of the Capitol. House Republicans are already locked in a pitched debate over larger government spending levels and have been unable to approve a budget resolution – not an ideal environment to pass emergency spending that isn’t required to be offset.  

And lengthy talks between Republican appropriators in the House and the administration have soured, with both sides largely talking past each other for weeks about what sort of response is needed.  

Democrats could also complicate efforts to send the package to the White House if they try to turn the Zika package into a vehicle to tag with other funding priorities.  

House Minority Leader Nancy Pelosi, D-Calif., said Thursday that Democrats would “absolutely” try to attach emergency spending to address the water crisis in Flint, Mich., as well as the epidemic of prescription drug abuse.  

“We would fight to have Zika, Flint and also opioids,” she said, adding that the opioids response “would require some outside-the-cap funding as well.”  

Lindsey McPherson and Jennifer Shutt contributed to this report.

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