The United Kingdom is no longer classified as being among the most stable and low-risk banking systems in the world, credit rating agency Standard & Poor's said on Thursday.

Britain's weak economy will continue to hinder the credit profile of its banking industry, S&P said in a report, adding it expected the unwind of high levels of debt to weigh heavily on economic growth prospects and banks' financial performance.

"We no longer classify the United Kingdom (AAA/Negative/A-1+) among the most stable and low-risk banking systems globally," Standard & Poor's Ratings Services said.