U.S. financial services company Citigroup has attracted significant interest by its plan to sell its Japanese contact center.

The contact center reportedly has little debt and strong cash flow, making it especially attractive to private equity firms. Major buyout firms Kohlberg Kravis Roberts (KKR), Permira, Blackstone and Bain Capital are all understood to be interested in buying the center, which is valued at up to $1billion.

Citigroup has reportedly been selling assets after it split its operations into a core banking group and a separate unit containing assets earmarked for sale. The company has raised nearly $9bn from asset sales in Japan during the past three months but delayed the sale of the Tokyo contact center until market conditions improved.