White House hopeful Sen. Bernie Sanders distinguished himself from Sen. Elizabeth Warren—another top competitor in the Democratic presidential primary—by highlighting their different beliefs on economic policy during an interview with ABC News chief White House correspondent Jonathan Karl that aired Sunday.

After ABC's Karl suggested that Sanders (I-Vt.) and Warren (D-Mass.) have "pretty close to identical positions" on major issues, Sanders said that "Elizabeth Warren has been a friend of mine for some 25 years and I think she is a very, very good senator, but there are differences between Elizabeth and myself. Elizabeth, I think, as you know, has said that she is a capitalist [to] her bones. I'm not."

Sen. Bernie Sanders tells @jonkarl that Sen. Elizabeth Warren is a "very, very good senator," but "there are differences between Elizabeth and myself." “Elizabeth, I think, as you know, has said that she is a capitalist through her bones. I’m not.” https://t.co/lAIleh47pV pic.twitter.com/pABeEeIKsa — ABC News Politics (@ABCPolitics) October 13, 2019

Sanders, a democratic socialist, went on to detail his concerns about "the situation today that we face in this country." Specifically, he called out major pharmaceutical companies for price fixing as well as the fossil fuel industry for profiting off of "destroying the planet." The senator, a champion of Medicare for All, also pointed out that the United States fails to guarantee healthcare to all people in the country, unlike other developed nations.

"I think business as usual and doing it the old-fashioned way is not good enough," Sanders said. "What we need is, in fact—I don't want to get people too nervous—we need a political revolution. I am, I believe, the only candidate who's going to say to the ruling class of this country, the corporate elite: Enough, enough with your greed and with your corruption. We need real change in this country."

Reiterating a key distinction between him and Warren on economic grounds, he said that "Elizabeth considers herself—if I got the quote correctly—to be a capitalist to her bones. I don't. And the reason I am not is because I will not tolerate for one second the kind of greed and corruption and income and wealth inequality and so much suffering that is going on in this country today, which is unnecessary."

Warren's quote which Sanders repeatedly referenced is from a July 2018 event hosted by the New England Council. The Massachusetts Democrat was quoted as saying, "I am a capitalist to my bones." During an interview about a week later, CNBC editor at large John Harwood asked Warren, "You don't think capitalists are bad people?"

"I am a capitalist. Come on. I believe in markets," Warren responded. "What I don't believe in is theft, what I don't believe in is cheating. That's where the difference is. I love what markets can do, I love what functioning economies can do. They are what make us rich, they are what create opportunity. But only fair markets, markets with rules. Markets without rules is about the rich take it all, it's about the powerful get all of it. And that's what's gone wrong in America."

Sanders is currently third in national polls for the crowded 2020 primary race, behind Warren and former Vice President Joe Biden, who is back in the top spot after Warren briefly took the lead earlier this week, according to RealClearPolitics.

Reporters and political observers noted that Sanders' comments during the ABC interview were "the biggest contrast" he has made with Warren in the race so far.

This is the biggest contrast Bernie Sanders has made with Elizabeth Warren to date: “I am ... the only candidate who's going to say to the ruling class,” and, "Elizabeth, I think, as you know, has said that she is a capitalist through her bones. I'm not." https://t.co/KeDYlPAaHG — Holly Otterbein (@hollyotterbein) October 12, 2019

The interview comes as Sanders has temporarily suspended campaign events to recover from a minor heart attack, which he also addressed Sunday.

"'Heart attack' is a scary word," he told Karl. "What I had is a 45 to 50 minute procedure, two stents were placed in my heart, because I had a blocked artery. This is a procedure, as I understand it, done many, many hundreds of thousands of times a year. It's a fairly common procedure, and people are back on their feet pretty soon, as is the case with me."

NEW: "I'm feeling very well. I look forward to the debate. I look forward to getting back to a very vigorous campaign," Sen. Bernie Sanders tells @jonkarl, adding that the campaign will release all of his medical records "as soon as we can" https://t.co/lAIleh47pV pic.twitter.com/EyxBuh2Rxe — ABC News Politics (@ABCPolitics) October 13, 2019

Sanders' campaign has said that he will participate in the upcoming Democratic primary debate co-hosted by CNN and The New York Times at Otterbein University in Westerville, Ohio, which will air at 8 pm Tuesday. The campaign announced Saturday that Sanders will host a public "Bernie's Back" rally at Queensbridge Park in New York City on the afternoon of Oct. 19.

Amid an emerging corporate media narrative that the heart attack dealt a devastating blow to Sanders' chances of winning the White House, Common Dreams reported Thursday that "prominent campaign surrogates, advisers, and supporters in recent days have forcefully pushed back against that notion and argued Sanders—with his grassroots army as enthusiastic and motivated as ever—is well-positioned to compete for and ultimately win the 2020 Democratic presidential nomination."

As RoseAnn DeMoro, former executive director of National Nurses United and prominent Sanders backer, told The Associated Press, "Heaven help the opposition."