Sen. Patty Murray, D-Wash., told reporters that she still prefers Obama's proposal but has reached agreement with Sen. Roy Blunt, R-Mo., on the smaller measure, which is likely to be added next week to a bill funding veterans and transportation programs.
The administration requested emergency funding to battle Zika in February but Republicans controlling Congress have been slow to react, and instead forced the administration last month to tap more than $500 million worth of unspent Ebola funding to battle Zika.
Polls show that the public isn't anywhere nearly as scared of Zika as it was about the Ebola outbreak in West Africa and the handful of cases in the U.S. in 2014, but Zika awareness and anxiety is likely to grow as mosquito season heats up.
The Senate move is likely to set up a conflict with the House, where GOP leaders are likely to press for a much smaller amount and pay for it by cutting other programs or using leftover Ebola money that was passed at the end of 2014.
The Senate measure would also preserve an administration program that would use some of the leftover Ebola money to help poorer nations build up their health infrastructure.
