Bernie Sanders isn't backing down from his critique of General Electric (GE - Get Report) -- he's taking it further.

The Democratic presidential candidate fanned the flames of his ongoing feud with the conglomerate in an interview aired on CNN's "State of the Union" Sunday, calling GE "greedy" and saying that his original comments about the company were "valid."

"Here is a corporation that has shut down plants all over this country, moved to countries where they could find the cheapest possible labor," he told correspondent Jake Tapper. "In fact, the guy who was head of General Electric before Jeff Immelt, he basically said that he'd like to see his manufacturing plants on a barge so they can move to the cheapest labor."

His remarks referenced Jack Welch, CEO of GE from 1981 to 2001, who in 1998 mused: "Ideally, you'd have every plant you own on a barge to move with currencies and changes in the economy."

Senator Sanders on Sunday also claimed that GE "in a given year, paid nothing in federal income taxes" and said the firm is "part of lobbying efforts in Washington to protect the interests of the wealthy."

"I think General Electric is a company that is well known for negotiating contracts with its workers which call for concessions, sending jobs outside of this country and not paying their fair share of taxes," he said. "That is, I think, a greedy corporation."

Tapper pushed back slightly, asking the Vermont senator why he hadn't leveled the same accusations at Apple, which also manufactures many of its products abroad.

Sanders explained that he uses GE as an example, though he conceded the tech giant is a guilty party as well. "You're right, Apple does manufacture a lot of their products in China, and I sure as heck would like to see them, and if I have anything to do with it, and I will, as president, to try to bring back manufacturing to the United States of America," he said.

Sanders' comments, first reported by Bloomberg, are just the latest chapter in a battle against GE that has intensified in recent days.

He criticized the firm in an April 1 interview with the New York Daily News editorial board, accusing the company of "greed" and "selfishness" and having a "lack of respect for the people of this country." He invoked it as an example of a company that is "destroying the moral fabric" of America.

GE chief executive Immelt subsequently hit back at Sanders' comments in a letter published in the Washington Post on April 6, accusing the senator of "missing the point" in his criticism.

"It's easy to make hollow campaign promises and take cheap shots in speeches and during editorial board sessions, but U.S. companies have to deliver for their employees, customers and shareholders every day," he wrote. "GE operates in the real world. We're in the business of building real things and generating real growth for a nation that needs it now more than ever."

Immelt also wrote that Sanders had never visited GE's aviation plant in his home state of Vermont -- something Sanders said on Sunday is a lie. "He's not telling the truth," he told Tapper.

TheStreet's Jim Cramer weighed in on Sanders' latest remarks, landing firmly on the side of CEO Immelt.

"I think that Sanders forgets that Jeff could move that plant to Mexico tomorrow next to the Bombardier plant in Queretaro where workers are paid $3 an hour, there is universal health care and pollution laws are unimportant," he said. "He chooses not to because he values American workers and wants to preserve as many jobs as he can."

As for Sanders' invocation of Welch, Cramer noted that Immelt has his "own philosophy" for GE. "Last I looked, blaming Jeff for Jack's ways seems both lame and irresponsible and, frankly, childish," he said.

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Neither GE nor the Sanders campaign immediately responded to request for comment on the senator's latest remarks.