House Ways and Means Chair Paul Ryan, R-Wis., says Republicans need to have a plan in place by June 20 to respond if the U.S. Supreme Court strikes down subsidies in up to 37 states.

A ruling in the King v. Burwell case, which challenges the legitimacy of insurance subsidies in states that haven't established their own exchanges, is expected near the end of June.

“We have to have a contingency plan already in place by the time the ruling comes out,” Rep. Ryan said on a call earlier this month with state legislators organized by the Foundation for Government Accountability, which has been pushing states to reject the Affordable Care Act's Medicaid expansion and to not establish their own exchanges.

Rep. Ryan also indicated that Republicans plan to use the budget reconciliation process to pass legislation to assist the millions of individuals who would lose access to subsidies if the plaintiffs prevail in the lawsuit. That process is seen as key to passing anything in the Senate because it only requires 51 votes, rather than the 60 votes typically needed to move legislation. However, Rep. Ryan also acknowledged that any package passed by Republicans is almost certain to draw a presidential veto.

“I think you're going to see this become very partisan,” Rep. Ryan said. “I think the president is going to try and enforce party discipline.”

Rep. Ryan has provided few specific details about what the Republican plan to deal with the fallout from a King ruling would look like. An op-ed piece he co-authored in the Wall Street Journal earlier this month indicated that some form of tax credits for low-income individuals would be part of the package.

Rep. Ryan is among the most influential members of the House. He has been the chief architect of controversial GOP proposals to overhaul Medicare and Medicaid in order to bolster their long-term financial viability.

On the call, Rep. Ryan implored state officials not to buckle under pressure if subsidies are struck down and there's a clamor to establish marketplaces in their states. “This law will not last,” Rep. Ryan predicted. “It will implode under its own weight. The last thing anybody would want to do, even if you're not a conservative, is consign your state to this law.”

Rep. Ryan also suggested that there would be time to act if the Supreme Court strikes down subsidies. He pointed to a suggestion by conservative Justice Samuel Alito during oral arguments earlier this month that a decision could be stayed for some period of time in order to mitigate the immediate harm to exchange customers.

“It's not going to be as if in a few weeks all these people in our states, my state included, are going to be out of subsidies,” Rep. Ryan predicted. “There's no rush to do anything.”

Paul Demko writes for Modern Healthcare, a sister publication of Business Insurance.