The backlash against the $54,000bn credit derivatives market gathered pace yesterday as US legislators renewed calls for regulating a sector widely blamed for contributing to the financial crisis.

“There is no question that we must adopt a stronger system of regulation,” Tom Harkin, the Democratic senator, told a Senate hearing on Tuesday. “It is hard for me to see how we are going to put our financial sector and our economy back on a sound footing unless we do so.”