The Bank of Shanghai plans to raise about 15 billion yuan ($2.39 billion) through an initial public offering (IPO) in Hong Kong this year to supplement its capital, according to an internal document circulated to the bank's shareholders.

The lender also plans to raise another 15 billion yuan via a public listing on the mainland, without giving a timetable. The planned listings are subject to the approval of the China Securities Regulatory Commission.

The bank launched an IPO plan in 2008, but has yet to complete the program. The lender is now contemplating extending the validity of the plan to May 2014.

The Bank of Shanghai is among several Chinese companies looking to raise funds outside the mainland IPO market, which has been frozen since November 2012. Regulators said there isn't an immediate timetable to re-launch the domestic IPO channel. More than 800 companies are waiting to get approval to be listed in Shanghai and Shenzhen.

The bank is considering issuing 5 billion yuan ($807.5 million) worth of subordinated debt in the domestic market to replenish its capital, if the application for the IPO in Hong Kong is turned down. The plan is to raise its capital adequacy ratio to meet regulators' demands.