Right after the merger of Travelers Group and Citicorp in 1998, Weill fired Dimon, abruptly ending a 15-year partnership that saw them build a financial services empire like no other at the time.
Dimon was doing "very well and he thought he was ready to run the company and he probably was," Weill admitted during a "Squawk Box" appearance. "But the only problem was, I wasn't ready to retire."
"So we began to not cooperate," Weill continued, "and that was not a good way to try and run a business."
Weill said he has not talked to Dimon recently, but joked that he's "open to receive a call, if he calls me."
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Weill also said the infamous "Greenbrier incident" involving Dimon and another executive did indeed happen. He described it as "a little fight on the dance floor," which happened at a company function at the West Virginia resort right after the Citigroup deal.