Federal Reserve Governor Jerome Powell urged Congress to rewrite the Volcker Rule, which restricts proprietary trading, while urging “a high degree of vigilance” against the buildup of financial risks amid improving U.S. growth.

“What the current law and rule do is effectively force you to look into the mind and heart of every trader on every trade to see what the intent is,” Powell said Saturday at the American Finance Association meeting in Chicago. “Is it propriety trading or something else? If that is the test you set yourself, you are going to wind up with tremendous expense and burden.”

Powell's comments compare to Fed Chair Janet Yellen, who has supported the sweeping bank rules of the 2010 Dodd-Frank Act in the wake of the global financial crisis. President-elect Donald Trump has vowed to dismantle Dodd-Frank. The Volcker Rule restricts banks with taxpayer-backed deposits from making certain types of speculative “proprietary” trades.