Federal Reserve Governor Daniel Tarullo said U.S. regulators must weigh objections raised by banks and governments to restrictions on proprietary trading under the Dodd Frank Act overhauling financial supervision.

“U.S. regulators will need to carefully consider the concerns that have been raised and the broader international implications of the Volcker rule as we work to finalize our implementing rules,” Tarullo said in testimony he plans to deliver to the Senate Banking Committee. The central bank released his comments today.

The regulation, named for its original champion, former Fed Chairman Paul Volcker, is intended to reduce the chance that banks through their investments will put depositors’ money at risk. It is one of the most contentious provisions of the 2010 Dodd-Frank Act.

Officials from Canada, Japan, the U.K. and the European Banking Federation have said in letters to U.S. regulators that the measure would impede global liquidity and harm international cooperation.

“There are also some elements of the Dodd-Frank Act that are unlikely to be pursued internationally in any comparable form,” Tarullo said. “There are not likely to be obvious answers to the resulting international complexities.”

Dodd-Frank requires that the ban on proprietary trading take effect by July 21, even if rule-making is still in progress. Fed Chairman Ben S. Bernanke said on February 29 that the central bank and other regulators won’t meet the July deadline to complete work on the rule.

The ban would include a two-year transition period. After that, the Fed could issue three one-year implementation extensions on a case-by-case basis.