New Delhi, Feb. 17 -- Thomas J. Pritzker, the billionaire heir to the Hyatt Hotels fortune and a central figure in the company's modern expansion, has stepped down as executive chairman with immediate effect, citing regret over his long-running association with Jeffrey Epstein and Ghislaine Maxwell.

In a letter to Hyatt's board on Monday, Pritzker, 75, said he was leaving to protect the hotel group from further reputational damage, acknowledging that his continued contact with Epstein after the financier's 2008 sex-crimes plea deal reflected a serious lapse in judgement.

Born and raised in Chicago, Illinois, Tom Pritzker is one of 13 billionaire heirs in the Pritzker clan and has long been among the most influential figures behind Hyatt...