Shares in Citigroup Inc rose 5 percent on their first trading day in Tokyo on Monday, in a new exchange listing designed to boost the U.S. bank's presence in Japan but which coincides with the departure of its CEO.

Charles Prince resigned as chairman and chief executive of Citigroup on Sunday and the bank said it may suffer an $11 billion write-down for subprime losses.

Robert Rubin, the former U.S. Treasury Secretary, was named chairman, while Sir Win Bischoff, who runs Citigroup's European operations, was named acting chief executive.

Traders said the changes were good for Citigroup but its Tokyo share rise may not reflect market sentiment due to limited trading volume.

It's positive for Citigroup that Prince quit, and it's also favorable to let off some steam before next week when I expect to see some more subprime-related turbulence, said Tsuyoshi Segawa, an equity strategist at Shinko Securities.

Segawa said he was paying little attention to the listing in Tokyo, with his focus much more on Citigroup's shares in the United States.

Shares in Citigroup rose from a tentative starting price of 4,330 yen, based on its New York close on Friday, to 4,550 yen by 0120 GMT, after first changing hands at 4,580 yen.

Major Japanese lenders including Sumitomo Mitsui Financial Group fell after financial stocks in New York were battered by fears that the worst of the credit crunch may still lie ahead.

Citigroup plans to use its shares to buy out minority shareholders in Nikko Cordial Corp, Japan's third-largest brokerage, for $4.6 billion, and has said it was moving to become the leading comprehensive banking and securities group in Japan.

That would give the U.S. firm full control of more than 100 brokerage outlets and a name well known to domestic investors in the world's second-largest economy, which has an estimated $13 trillion in household assets.

(Additional reporting by Aiko Hayashi)