Aetna CEO Mark Bertolini said the uncertainty surrounding the Affordable Care Act (ACA) and its insurance marketplace is too big of a risk for his company, saying it has “no intention of being in the market for 2018.”

Insurers will have to submit proposed premiums around April, but with the talk of repealing the law and no consensus behind a replacement, Bertolini said there’s little choice but to avoid the uncertainty altogether.

"Currently, where we stand, we'd have to have markets worked up ... prices worked up for April 2017 to apply, and there is no possible way that we'll be able to do that given the unclear nature [of where] that regulation is headed,” he said on Aetna’s quarterly earnings conference call.

Bertolini said he expected exchange risk pool to “continue to deteriorate,” but also predicted 2018 would be, at best, a transition year for any Republican-supported ACA replacement. While he isn’t supporting any particular replacement proposal yet, he did say the company is part of the repeal-and-replace conversation.

“We remain optimistic that the next wave of healthcare reform will focus on affordability, quality, and addressing the needs of the millions of Americans who remain uninsured or lack access to affordable healthcare,” he said. “To that end, we continue to actively engage in constructive dialogue with law makers and regulators and are committed to working towards preserving the positive aspects of the ACA and developing consumer-based approaches that deliver access to affordable quality healthcare to all Americans.”

Aetna had already pulled back on its exchange participation in 2017, offering coverage in four states, down from 16. This was partially due to losses of $450 million on that business, but according to the recent court ruling blocking the proposed merger with Humana, the moves were also motivated by the federal government’s antitrust lawsuit.

Bertolini did say the company is considering an appeal of that ruling, noting no decision has to be made until Feb. 15, when the merger agreement with Humana expires.