U.S. House Republicans are working on changes to their healthcare overhaul bill that would implement a work requirement for the Medicaid program for the poor, as well as boost tax credits for older, lower income people, U.S. House Speaker Paul Ryan said on Sunday.

"We think we should be offering more assistance than the bill currently does," for lower-income people age 50 to 64, Ryan said of the tax credits for health insurance that are proposed in the legislation.

Speaking on the "Fox News Sunday" television program, Ryan also said Republicans are working on changes that would allow federal block grants to states for Medicaid. Lawmakers plan to have the healthcare legislation on the House floor this Thursday, Ryan said.