BEIJING -- Non-performing loans (NPL) in China's commercial banks hit 433.3 billion yuan ($66.67 billion) at the end of the first quarter, a decrease of 300 million yuan from the end of last year, China's banking regulator said in Beijing on Friday.

Related readings:  Large banks rein in credit supply  China's top banks step up lending in April  Chinese banks can meet tougher standards: Official  Smaller banks face 'barrier'

Sub-prime loans accounted for 166.5 billion of the total NPL. Commercial banks' NPL ratios stood at 1.1 percent, unchanged from the beginning of the year, the China Banking Regulatory Commission said in a statement posted on its website.

In the first quarter, Chinese commercial banks made combined profits of 263.5 billion yuan. Their capital adequacy ratios, which measure the ability of a bank to deal with risk assets, dropped to 11.8 percent at the end of March, compared with 12.2 percent at the beginning of the year.

Lenders' provisioning ratios  rose to 230.2 percent by the end of March, up 12.5 percentage points from the end of 2010, the statement said.

Due to the government's intensified efforts to curb inflation, which have included raising interest rates and hiking reserve requirement ratios, lenders' liquidity has also been tightened. The statement said their liquidity ratios fell to 41.3 percent, compared with 42.2 percent at the end of December.