To optimize business potential, BEA China shifted its focus from expanding its onshore loan portfolio to arranging offshore loans for clients requiring funding for overseas business expansion.

As a result, the outstanding amount of standby letters of credit issued by BEA China to secure offshore borrowings for its customers grew significantly, generating fee income.

As of June 30, the outstanding number of standby letters of credit issued by BEA China in favor of the bank's business units in Hong Kong and abroad was up by 77.9 percent from the end of 2013.

This boosted the net fee and commission income of the corporate banking business by 37.5 percent year-on-year, the bank said. China, however, remains only a small part of overseas banks' business.

John Caparusso, banking analyst of Standard Chartered Bank (HK) Ltd, said: "Foreign banks are not constrained by the industrywide slowdown in China because their operation is tiny in the country, so the comparable base is quite small. Their growth in percentage terms is rapid, but in absolute terms, it's insignificant."

He said foreign banks in aggregate claim roughly 2 percent of total bank loans in the country. Even a large foreign bank like HSBC has a China market share that is well below 1 percent. None of them accounts for more than 0.5 percent.

But China is certainly an important market for foreign banks as the country is set to become the world's biggest economy at some point.

"While the physical presence of foreign banks remains small in the country, their market potential is significant. Their China business will continue to grow rapidly. Foreign banks are serious about China. They will definitely hang on," Caparusso said.

Financial experts like Wen expect that the opportunities China offers will have foreign banks allocate more resources in the country.

"As an emerging market, China is growing faster than many others, and the internationalization of the yuan has just taken off. We are optimistic about foreign banks' China business. We predict they will launch more new products to take advantage of the momentum in the country," Wen said.

He added that China operations look outstanding for foreign banks as many other markets suffered a bleak first half. Some banking giants were fined in the United States for regulatory violations. And Standard Chartered incurred a $127 million loss in South Korea and has since sold off parts of the business.

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