Republicans in the US House of Representatives will try to pass legislation this week providing US$622.1 million (NZ$917.33 million) in emergency funds to fight the spreading Zika virus, far less than the Obama administration has been seeking.
House Appropriations Committee Chairman Hal Rogers introduced the measure on Monday, according to a statement.
The bill would offset the new spending by taking US$352.1 million from an Ebola fund and another US$270 million from a Department of Health and Human Services administrative account.
The Obama administration and health officials have expressed concerns in the past with taking money from Ebola programs to pay for Zika virus efforts.
President Barack Obama in February called for US$1.9 billion in emergency funds that would not result in any government spending cuts elsewhere.
The House bill is also at odds with legislation being debated in the Senate.
Competing proposals there would either give Obama the full US$1.9 billion or at least US$1.1 billion.
The Senate is expected to cast initial votes on the alternatives on Tuesday.
If the House and Senate approve competing versions they would have to reconcile their differences and pass one uniform bill before sending it to Obama for signing into law.
The mosquito-borne Zika virus has been linked to severe birth defects and other neurological disorders and is beginning to show up in warm climates in US southern states such as Florida.
Of the US$622.1 million proposed by House Republicans, US$230 million would go to the National Institutes of Health to help support the development of vaccines to stop the spread of Zika.
Other funds would be contributed to global health programs, through the State Department and US Agency for International Development, and for the development of rapid diagnostic tests.