Berkshire Hathaway is Wells Fargo's largest shareholder, owning 9.51 percent of the outstanding shares as of the latest available filings.

Stumpf told the House Financial Services Committee on Thursday that he and Buffett had one conversation since the scandal broke, but would not elaborate.

"What Mr. Stumpf said in the House hearings today regarding a conversation with Warren Buffett is correct," Buffett's secretary, Debbie Bosanek, said in an email to Reuters.

Buffett previously told Fox News he would not comment on the scandal until November. On Thursday he shot down rumors he had expressed "extreme dissatisfaction," with Wells Fargo's board of directors, according to CNBC.

(Reporting by Dan Freed in New York; edited by Linda Stern in Washington D.C.)