LONDON (

TheStreet

) -- A top

Citigroup

(C) - Get Report

executive is leaving the bank for a likely job at the investment arm of U.K. bank

Barclays

(BCS) - Get Report

, a report says.

Tom King, Citigroup's London-based head of corporate and investment banking and capital markets for Europe, the Middle East and Africa, is leaving the bank after 20 years, the

Wall Street Journal

reports. King is expected to join Barclays to help the bank expand its European investment banking business. People familiar with the matter cautioned it is isn't yet certain that King will join Barclays, the

Journal

adds.

Citigroup has seen a string of defections is its investment-banking division on both sides of the Atlantic, the

Journal

reports. Barclays bought part of

Lehman Brothers

last year to strengthen its U.S. operations and is now trying to do the same outside the U.S.

Spokespeople for both banks declined to comment for the newspaper.

-- Reported by Joseph Woelfel in New York

.

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