Citigroups Mike Corbat will become its sole chief executive officer for Europe,the Middle East and Africa as part of a management shake-up,according to a media report. Corbat,the chief executive officer of Citi Holdings since January,2009,was named the sole chief executive of Citigroups business in Europe,the Middle East and Africa,a job was previously held by two executives,The Wall Street Journal reported. Bill Mills,one of the executives to be replaced by Corbat,will head Citis North American banking operations. The other executive,Alberto Verme,would remain in the region as chairman of Banking for Europe,the Middle East and Africa,it added. The report also said the bank also gave Manuel Medina-Mora additional oversight of all of Citigroups consumer and commercial-banking businesses worldwide. He previously served as the head of consumer banking for the Americas. Citigroup said the Japanese division,formerly part of the Asian-Pacific region,would operate as a standalone region. The division would report directly to John Havens,the companys chief operating officer,who is based in the US,it added. All changes would be effective January 1,the report said,citing a note to employees by CEO Vikram Pandit and John Havens,Citigroups chief operating officer. The report said moves are designed to groom executives,so Citigroup will have a pipeline of leaders ready to step in whenever Pandit decides he is ready to step down,a decision that is not expected for several years at least.