Trump told the WSJ that he may withhold payments to health insurers to force Democrats to negotiate on health care.

He said the executive branch may lack legal authority to issue the payments, which reduce costs for low-income customers:

"I don't want people to get hurt. What I think should happen—and will happen—is the Democrats will start calling me and negotiating."

Why it matters: Trump's comments threaten to escalate not just the battle with Democrats, but the uncertainty among insurers, which are already saying they may have to pull out of the Obamacare markets or raise premiums if they don't know what's going to happen with the payments.