The major banks generally increased write-offs and transfers of bad loans to keep their NPL ratios at a low level last year.

CCB cleaned up 48.5 billion yuan worth of nonperforming loans in 2013, including write-offs of 15.7 billion yuan.

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ICBC wrote off 16.5 billion yuan of bad loans last year, more than doubling the 7.53 billion yuan in 2012.

ABC also more than doubled its write-offs and "transfer-out" to 9.78 billion yuan, which in part contributed to the drop of its NPL ratio to 1.22 percent in 2013 from 1.33 percent in the previous year.

The "Big Four" banks tightened their grip on nonperforming loans after the China Banking Regulatory Commission warned of asset quality risks.

"We are following our asset quality closely," said Chen Siqing, president of BOC.

In 2013, BOC cut its loans to local government financing vehicles by 11.24 percent from the previous year to 353.5 billion yuan. Its loans to industries with excess capacity fell 7.8 percent to 188.5 billion yuan.

By the end of 2013, ICBC reduced its outstanding loans to LGFV by 94.3 billion yuan, to the property market by 8.6 billion yuan and to industries suffering from excess production capacity by 19.9 billion yuan from the previous year.

Compared with major State-owned banks, the assets of smaller banks deteriorated faster as they chose higher-risk projects.

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