Citigroup is planning to shift the headquarters of its European retail banking operation to Dublin from London to benefit from lower costs and capital requirements.
This week the bank wrote to clients to say the UK-based business, Citibank International Limited, which operates a small number of branches across some 20 European countries, would be taken over by Dublin-based Citibank Europe Plc.
"From a strategic perspective for Citi, moving to a single pan-European bank is expected to reduce operational and regulatory complexity, capital requirements and cost," the company told clients.
Analysts said UK rules that require banks to hold a higher level of cash in reserve than other European countries do was likely to be a factor behind the move but that they did not expect to see a stream of other banks leaving the UK.
"The primary reason is simplification, mirroring Citi's strategy of creating a simpler, safer, stronger institution," a spokewoman for the bank said.
She said the move would not lead to any job losses.