Billionaire Warren Buffett, who has profited from investing in banks while faulting the financial industry's lapses, said Senator Elizabeth Warren's approach to Wall Street is too confrontational.

"She would do better if she was less angry and demonized less," Buffett said Monday in an interview on CNBC. "I believe in 'hate the sin, and love the sinner.'"

Warren, a Democrat from Massachusetts, was elected to the Senate in 2012 and has won popularity among some party members by her willingness to challenge big banks. She wrote in a Huffington Post opinion piece in November that it was time to "loosen the hold that Wall Street banks have over economic policy making."

She was criticizing President Barack Obama's nomination of Antonio Weiss to a Treasury Department post. The former Lazard Ltd. dealmaker later withdrew and took a separate job as counselor to Secretary Jacob J. Lew, a role that doesn't require Senate confirmation.

Buffett's remarks Monday represented a harsher tone than he took in 2011 when he said that Warren had made a lot of enemies in working to establish the Consumer Financial Protection Bureau, and that her efforts were necessary to curb excesses in the financial industry.

"It's clear, you need a policeman," he said in an interview with Bloomberg Television at the time. "And she's a pretty good policeman."

The billionaire has long supported causes popular among Democrats, such as higher taxes on the wealthy and protecting access to abortions. And while he is backing Hillary Clinton for president, he said on CNBC that he supports some Republicans and wants more comity between the parties.

"In the end, we do have to work together," Buffett said. "It does not help when you demonize."

Matt Cournoyer, a spokesman for the senator, had no immediate comment Monday.

Buffett's Berkshire Hathaway Inc. has the largest stake in Wells Fargo & Co., the biggest bank in the U.S. by market value, and also has investments in Goldman Sachs Group Inc. and Bank of America Corp. While he faulted bankers for their fees as recently as his annual letter on Saturday, he has long sought to blunt the edge of his critiques.

"I don't look at Wall Street as evil," he said in a 2009 interview with Business Wire, a Berkshire subsidiary. "I look at Wall Street as given to huge excess sometimes. I don't want to get rid of it. We need something to allocate capital and distribute securities and all of that throughout the system. We have got a big capitalist system and we have to have a big capital market — but there is plenty of room for improvement."

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