Regulators implementing the Dodd-Frank Act face questions from U.S. lawmakers today over progress on required new rules, including provisions of a proposal to bar Wall Street firms from proprietary trading.

The Treasury Department, Federal Reserve and other financial regulators have spent more than a year drafting rules required by the law, which also includes new regulations for the $708 trillion global swaps market, tools to wind down failing financial firms and enhanced supervisory powers over the largest and most interconnected companies.

"The ultimate shape of both individual requirements and overall reform is becoming clearer by the week," Neal Wolin, the deputy Treasury secretary, said in remarks prepared for the Senate Banking Committee hearing. "Increasingly, financial firms are in a position to adjust their business models in anticipation of final rules."