China's banks extended a surprisingly large amount of new loans in June, more than doubling that of May's, while driving up possibilities of bad loans and excessive production capacity amid a credit boom.

Preliminary calculations showed that new lending was 1.53 trillion yuan, the central bank said on its website yesterday, bringing total lending this year to 7.4 trillion yuan, far exceeding the country's initial full-year target of disbursing 5 trillion yuan in loans. Total lending so far this year amounted to almost one quarter of last year's GDP.

June's figure was the third-biggest monthly sum this year, after the 1.89 trillion yuan lent in March and the 1.62 trillion in January.