President Donald Trump recently made his boldest claim yet in his longstanding promise to lower drug prices.

“You know, we’ve cut drug prices by 1,200, 1,300 and 1,400, 1,500%,” he told reporters on Sunday, noting the reductions will start over the next two to three months. “I don’t mean 50%. I mean 14- 1,500%.”

Trump has unveiled a number of moves aimed at cutting drug prices in recent months, but he has yet to move the needle on reducing costs – much less slashing them by 1,500%, which is mathematically impossible, experts say.

Just how much Trump will be able to accomplish is a matter of debate.

“The administration, by itself, has relatively limited power to affect drug prices across the US market,” Benedic Ippolito, a senior fellow in economic policy studies at the right-leaning American Enterprise Institute, told CNN. “Congress has tons of power, but the administration, if they’re acting by themselves, there’s just only so much they can do.”

Still, Trump’s comments are signaling “strong political will,” and it would be unwise for drugmakers to dismiss them, said Milena Sullivan, policy practice director at Avalere Health.

“President Trump already has a track record of disruptive policymaking and a willingness to push the limits,” she told CNN. “The rhetoric has only been intensifying. Even if the math doesn’t make sense, the political message is serious.”