Paul said on CBS's "Face the Nation" that Ryan was being misleading in presenting supporters of the bill, which is backed by President Donald Trump, as being inflexible when, in fact, Trump has signaled he is open to negotiations on the legislation.
"You know what I hear from Paul Ryan? 'It's a binary choice, young man,'" Paul said. "But what does a binary choice mean? His way or the highway."
The Kentucky senator said he rejected the premise that the President would not negotiate on the bill and anticipated that Ryan would not get the legislation, as written, through Congress.
"He will not have the votes," Paul said.
Paul railed against the bill, which he alternatively labeled "Obamacare Lite" and "Ryan's plan," saying it would not fix major problems in the health insurance market. He predicted that the Congressional Budget Office's estimate of the impact of the legislation would show it would cover fewer people than Obamacare.
"CBO is going to come out and say a lot of people are not covered," Paul said.
The bill backed by Ryan and the President, dubbed "the American Health Care Act," would repeal Obamacare's individual mandate requiring all people to have health care coverage, but it also would force people to pay a premium surcharge if they have a gap in coverage and then buy a policy on the individual market.
For this and other reasons, some analysts have said the bill would lead to a large drop in coverage. The CBO is expected to issue its assessment of the bill this week.
Ahead of that assessment, Ryan has slightly altered his messaging, indicating the CBO would say the bill would cover fewer people than the Affordable Care Act, but adding that this was not a fault of the bill, but an indication of economic "freedom."
In a separate interview with CBS that aired Sunday, Ryan said, "The one thing I'm certain will happen is CBO will say, 'Well, gosh, not as many people will get coverage.' You know why? Because this isn't a government mandate."
"We're not going to make an American do what they don't want to do," Ryan said. "You get it if you want it."
Pressed to provide an estimate of the number of people who would lose coverage if his bill became law, the Wisconsin Republican said, "It's up to people."
Ryan made similar comments in an interview
on Friday with the conservative radio host Hugh Hewitt.
"We always know you're never going to win a coverage beauty contest when it's free market versus government mandates," Ryan said. "If the government says, 'Thou shall buy our health insurance,' the government estimates are going to say people will comply and it will happen. And when you replace that with, 'We're going to have a free market, and you buy what you want to buy,' they're going to say not nearly as many people are going to do that. That's just going to happen."