Federal Reserve Chairman Ben Bernanke says the central bank is working closely with other regulators to implement the biggest overhaul of the U.S. financial rules since the 1930s.
The law enacted last year aims to protect the country from another financial crisis like the one that hit in 2008 and plunged the economy into a deep recession.
The Fed chief testified at a Senate Banking Committee hearing Thursday that work is under way to set up a government agency housed within the Fed for protecting consumers from abusive financial practices.
Republicans escalated their push to delay and defund the Dodd-Frank Wall Street reforms at the hearing.
Democrat Tim Johnson, replacing Christopher Dodd, gaveled open his first committee hearing amid calls by Republicans in the Senate and the House of Representatives for a slow-down in Dodd-Frank implementation.
Johnson said at the hearing's opening that he will defend "the letter and spirit of the new law," while cautioning that its "global impact must be (handled) with great care to avoid unintended consequences that could impair economic growth or send good paying jobs overseas."
For banks and Wall Street, the hearing will be another act in a long-running drama that analysts expect will lead to few, if any, changes in the landmark reforms approved last year in the wake of the 2007-2009 financial crisis.
"The fact that it's Johnson's first hearing is interesting and may provide clues about the direction of the committee," said Brian Gardner, policy analyst at the investment firm of Keefe Bruyette & Woods.
"Republicans will argue in favor of extending implementation of (Dodd-Frank) ... but these are timing issues and won't affect the substance of the rules," Gardner said.
From derivatives oversight to bank capitalization, the financial regulation issues being debated on Capitol Hill will also feature in a Paris meeting on Friday and Saturday of Group of 20 finance ministers and central bank chiefs.
With international coordination of post-crisis reforms still a serious challenge before policy-makers, Senator Richard Shelby urged a Dodd-Frank slow-down.
"Regulators must not compound the mistakes of Dodd-Frank by promulgating uninformed rules," said Shelby, the committee's top Republican member, at the hearing.
Testifying before Johnson's committee will be Federal Reserve Chairman Ben Bernanke and the heads of the Securities and Exchange Commission, the Commodity Futures Trading Commission, the Federal Deposit Insurance Corp and the Office of the Comptroller of the Currency.
The Fed, the SEC and the CFTC must put into practice hundreds of new rules stemming from Dodd-Frank, written and passed by congressional Democrats and President Barack Obama over the fierce opposition of Republicans and Wall Street.
"Chairman Johnson will be active in ensuring that (Dodd-Frank) is implemented as planned," said Edward Mills, policy analyst at investment firm FBR Capital Markets.
Aides said Johnson will likely raise questions at some point, however, about limits imposed by Dodd-Frank on debit card fees. South Dakota is a credit card business hub.
A separate hearing on the card fees rule will occur on Thursday in the House Financial Services Committee, which is now under Republican control.