(MCT) — WASHINGTON — The Obama administration stepped up pressure on states Monday to guarantee health insurance for all their low-income residents in 2014 under the Affordable Care Act, warning governors that the federal government will not pick up the total cost of expanding coverage only partially.

“We continue to encourage all states to fully expand their Medicaid programs and take advantage of the generous federal matching funds to cover more of their residents,” Secretary of Health and Human Services Kathleen Sebelius wrote in a letter to governors.