Pandit is known among his colleagues as a clam executive and the Journal said he is expected to make structural changes that are already under consideration.

"Some business lines may be cut and others reorganised," the paper quoted a person familiar with the studies as saying.

"A broad cost-cutting plan to supplement one initiated by Prince is likely. While Citigroup executives are already hammering out details, the final decisions will likely wait for several weeks after Pandit has settled into the job," the person, who was not identified, told the Journal.

Wall Street analysts said investors would be closely watching Pandit's steps. His agenda, an analyst on CNNMoney said, will initially be influenced by the immediate severity of bad loan losses and other pressing problems at Citigroup.

But within his first month, investors will also want a clear indication of where he stands on important longer-term questions, like whether large parts of the bank should be sold off.

Pandit serves on the boards of Columbia University, Columbia Business School, India School of Business Hyderabad, India and the Trinity School (NY). He is a former board member of Nasdaq, New York City Investment Fund, American India Foundation and the Council on US Competitiveness.

He earned a Ph.D in Finance from Columbia University. He also holds a Master's degree and a Bachelor's degree in electrical engineering from Columbia University.

Citi has some 200 million customers in more than 100 countries, and provides consumers, corporations, governments and institutions with a broad range of financial products and services, including consumer banking and credit, corporate and investment banking, securities brokerage, and wealth management.

Citi's major brand names include Citibank, CitiFinancial, Primerica, Smith Barney and Banamex.