By Enda Curran 

HONG KONG--A senior banker at a state-owned Chinese bank is embroiled in two lawsuits, one where he is defending himself against his former employer and another where he is demanding his money back from his personal bank, which he alleges lost a part of his wealth with risky bets.

Zhang Hongli is now a top executive at Industrial & Commercial Bank of China Ltd., China's largest state-owned bank by assets, and is one of the best known bankers in the country, having previously held top China banking jobs at Deutsche Bank AG and Goldman Sachs Group Inc. He is also one of the few executives from a foreign bank to have served on the Chinese People's Political Consultative Conference, a government advisory body.

He is being sued by Deutsche Bank for $6.3 million that the German lender claims it is owed after court documents allege he "induced" the bank to transfer him money at an unspecified date before he left the bank in 2010 to join ICBC as executive vice president.

Deutsche Bank's suit against Mr. Zhang is seeking damages, which include a principal sum of nearly $4 million with the remainder in interest, according to Hong Kong court documents dated Aug. 8.

In court papers, Deutsche Bank accused Mr. Zhang of "misrepresentations" which "induced" the bank to transfer nearly $4 million to a bank account in the name of Harperskille Ltd. with China Merchants Bank, Shenzhen branch. The papers don't provide further details about the claims, nor do they say when the court case is scheduled to be heard.

Mr. Zhang couldn't be reached for comment. His lawyer didn't comment.

Separately, Mr. Zhang, his wife, and the trustees of his family investment trust are plaintiffs in a suit against Singapore's DBS Group Holdings Ltd., alleging that their investment vehicle, Wise Lords, lost millions of dollars after it was sold complex foreign-exchange products that turned sour during the financial crisis. The plaintiffs claim an alleged breach of trust with DBS and say they didn't understand the risks involved with the investments.

The court case against DBS, which awaits a judge's verdict, was heard in Hong Kong's High Court in October and didn't get much attention. The original writ for the case was filed by Mr. Zhang and his wife, Ji Zhengrong, in February 2011, according to court documents.

In court, lawyers for DBS argued that Mr. Zhang, as a senior executive at one of the world's largest banks, and his wife were sophisticated investors, noting that Ms. Ji was university-educated and steered the investment decisions for Wise Lords.

"There is zero scope in this case for a story of innocent naïfs being bamboozled by a big bank," lawyers for DBS argued in court, according to court documents.

Investments made by Wise Lords at different periods included emerging market mutual funds and natural resources funds, investments in Chinese stocks and later currency trades that built up substantial Australian dollar, euro and U.S. dollar decumulators, court documents show. A decumulator is a contract that obliges investors to sell, Mr. Zhang's case, a currency at a fixed price, on a frequent basis.

"DBS Group takes the plaintiffs' allegations very seriously. DBS Group is satisfied the claims made by Mr. Zhang and his wife are without merits and will not succeed. All of the claims made were denied and vigorously defended. DBS Group is confident the claims will be dismissed, " the bank said in emailed response to questions.

Foreign banks have typically been known to go to great lengths to build relations with Chinese officials in the hope of winning lucrative contracts from large state-owned corporations, so it is unusual to see cases like Mr. Zhang's on a public stage. When Mr. Zhang's left Deutsche Bank in 2010, it lauded his record and described his departure to ICBC as the first senior executive to be hired by a Chinese bank from a foreign bank. The departure was announced by the German bank in a release titled "Deutsche Bank confirms Lee Zhang to follow government call."

Write to Enda Curran at enda.curran@wsj.com

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