WASHINGTON (AP) — Democratic governors Wednesday warned top Republicans in Congress that repealing the Obama health care law would stick states with billions of dollars in costs for providing medical care to residents made newly uninsured.

The Democratic Governors Association wrote to House Speaker Paul Ryan and Senate Majority Leader Mitch McConnell. Governors estimated that states could face nearly $69 billion in costs for uncompensated care over the next 10 years if the health law is repealed. States traditionally shouldered a hefty share of such costs.

Republicans plan to repeal “Obamacare” early next year, then take up to several years to replace it. During the interlude, party leaders have promised an orderly transition to a new system. It’s unclear what that would involve, but presumably some of the law’s popular provisions — such as subsidies and protection for those with pre-existing medical conditions — would be kept in place.