NEW YORK ( TheStreet) -- Citigroup ( C) could shake up its top management in Japan following a regulatory investigation, The Wall Street Journal reported, citing people familiar with the matter. The investigation, the Journal said, found alleged problems with the bank's disclosures when selling financial products, including a failure by Citigroup to provide mutual-fund investors with prospectuses in a timely fashion. No decision has been made, according to the newspaper, but one option being considered is a shuffling of senior Citigroup executives to include more Japanese managers, the people said. Officials also are considering installing a chief operating officer for Citigroup's banking operations in Japan, as well as more direct oversight by executives in the bank's New York headquarters. The Journal reported Friday that Japan's Financial Services Agency could issue sanctions as early as October against the local arm of Citigroup. The fate of Darren Buckley, CEO of the banking unit Citibank Japan, isn't clear, according to the Journal. -- Written by Joseph Woelfel >To contact the writer of this article, click here: Joseph Woelfel >To submit a news tip, send an email to: email@example.com.