The head of China's largest credit rating agency has criticised western counterparts for causing the global financial crisis and said that, as the world's largest creditor nation, China should have a bigger say in how governments and their debt are rated.

“The western rating agencies are politicised and highly ideological and they do not adhere to objective standards,” Guan Jianzhong, chairman of Dagong Global Credit Rating, told the Financial Times in an interview.

“China is the biggest creditor nation in the world and, with the rise and national rejuvenation of China, we should have our say in how the credit risks of states are judged.”

Mr Guan argued that Moody's Investors Service, Standard & Poor's and Fitch Ratings – the three companies that dominate the global credit rating industry – had become too close to the clients they were supposed to be objectively assessing.

He criticised the practice of “rating shopping” by companies that offer their business to the agency that provides the most favourable rating.

Western rating agencies have been widely criticised by policymakers, regulators and investors in developed economies for handing out top-notch triple A ratings to structured products that turned toxic after the financial crisis.

They have also been criticised for being too slow to downgrade some of the heavily indebted eurozone economies, most notably Spain, which still holds triple A ratings from Moody's.

There is also a view among many investors that the agencies would shy away from withdrawing triple A ratings to countries such as the US and UK due to political pressure.

Last week, privately owned Dagong published its own sovereign credit ranking . The results were very different from those published by Moody's, S&P and Fitch, with China ranking higher than the US, the UK, Japan, France and most other big economies.

Dagong, which was established in 1994, has about 25 per cent of China's fledgling credit rating market, while subsidiaries of the big three global agencies control most of the rest.

Dagong's next goal is to break into the international market, starting with the US. But even if it can overcome reluctance from US regulators, it may have a hard time convincing international clients of its objectivity, considering the nationalistic tone it strikes at home.