NEW YORK, Sept 16 (Reuters) - Citigroup Inc (C.N) is hiring Steve Milovanovic to head its investment banking unit which focuses on mergers and acquisitions by financial institutions in the Americas, according to an internal memo seen by Reuters on Thursday. Milovanovic will join from Goldman Sachs Group (GS.N), where he was co-head of M&A for the financial institutions group (FIG) in the Americas, said the memo, the contents of which were confirmed by a Citigroup spokesperson. "Steve’s experience, judgment and client relationships will further strengthen Citi’s strategic advisory capabilities," the memo said, noting that Milovanovic will be based in New York. Milovanovic, who has also worked at Credit Suisse Group (CSGN.S) in his banking career, has more than 20 years of dealmaking experience, with a focus on financial services.