Improved balance sheets and economic growth have helped bump up the credit ratings of 10 mainland commercial banks from a year ago, a report said Tuesday.

"We analyzed the performance of 16 banks over the past year and we're positive about their credit status, especially given the improving fundamentals," said Li Li, general manager of financial institution ratings at China Chengxin International Credit Rating Co, which put out the report.

Compared with five banks that were rated AAA last August, seven got the top rating this year, with China Merchants Bank and China CITIC Bank Corp Ltd upgraded from AA+ and AA respectively.

Higher risk resistance and profitability as well as improved asset quality and capital adequacy ratios helped to lift the banks' ratings.

"The banks' profit growth will slow in the foreseeable future, but growth momentum will continue. Based on bank forecasts, as long as GDP growth stays above 8 percent, asset quality won't be affected too much," Li said.