Washington (CNN) Democratic presidential candidate Sen. Bernie Sanders on Monday stressed the differences between his single-payer health care plan and a new proposal from Sen. Kamala Harris, labeling her approach "not ' Medicare for All.' "

Harris' plan, which was released Monday, would put the US on the path toward a government-backed health insurance system over the course of 10 years but stops short of completely eliminating private insurance. The future of health care in America has marked a rare point of difference in the crowded 2020 Democratic field.

"Well, first of all, I like Kamala. She's a friend of mine, but her plan is not Medicare for All," Sanders told CNN's Jake Tapper on "The Lead," hosted from Detroit on Monday. "What Medicare for All understands is that health care is a human right and the function of a sane health care system is not to make sure that insurance companies and drug companies make tens of billions of dollars in profit."

"The function of Medicare for All is to guarantee health care to all people as soon as possible," Sanders continued.

Speaking to Harris' goal to achieve Medicare for All in 10 years, Sanders said, "We think that four years is as long as it should be, not 10 years."

"And that's one of the reasons I disagree with Sen. Harris," he added.

Members of the Sanders campaign flooded the airwaves in defense of Medicare for All and against Harris' plan on Monday.

"Unfortunately, I think we've seen two major changes," Faiz Shakir, the campaign manager told CNN's Poppy Harlow on "Newsroom."

"One is she's decided she would like to privatize Medicare. She would like to introduce more insurance companies into Medicare. That introduces more corporate greed and profit seeking into Medicare. The second thing she wants to do is phase it in over 10 years, not in one term of a presidency, not in two, but that you would have to wait 10 years for people who have been struggling."

Shakir pointed out that Harris has not signed on to the pledge put forth by the Sanders campaign to reject donations from pharmaceutical executives as another sign that her campaign does not have its priorities right on health care.

"I don't believe Kamala Harris said she would take that pledge," Shakir said. "What that means is are you willing to fight these health insurance companies and pharmaceutical companies when you're in the Oval Office. And I don't think we know that. I don't think we have confidence. And obviously the plan here is suggesting that there's some concern over taking them on."

Josh Orton, the Sanders campaign's policy director, told CNN, "It's bad policy, bad politics, and compared to Medicare for All it vastly expands the ability for private insurance corporations to profit from overbilling and denying care to vulnerable patients who need it the most."

On the role private insurance companies play in Harris' plan, the Sanders campaign's chief of staff Ari Rabin-Havt, told CNN, "It would give a lot of money and a lot of power to private insurance companies over people's health care, and that's not what we believe in."

Harris' proposal seeks to occupy a middle ground between Medicare for All champions like Sanders and Massachusetts Sen. Elizabeth Warren and more moderate voices on health care like former Vice President Joe Biden, who has advocated for reforms to the current system.

Harris wrote in a post outlining her plan that Medicare would "set the rules of the road."

"We will allow private insurers to offer Medicare plans as part of this system that adhere to strict Medicare requirements on costs and benefits," she said. "Medicare will set the rules of the road for these plans, including price and quality, and private insurance companies will play by those rules, not the other way around."

Warren told CNN Monday that while she hadn't "seen the details" of Harris' plan, she emphasized her support for Medicare for All.

"I'm not here to attack other Democrats. I'm here to talk about what I believe in," she said. "And as I've tried to make clear, I believe that health care is a basic human right. And I will fight for basic human rights. That means Medicare for all as the best possible way to give us maximum coverage at the lowest possible cost."

"Medicare for All critics tell us that Americans just love their private health insurance companies," Sanders said earlier this month. "You know what? I have never met one person who loves their insurance company."