Republicans lawmakers on Tuesday started trying to kill a brand-new U.S. rule prohibiting banks and credit card companies from requiring customers who open new accounts to sign an agreement that they will not join a group lawsuit in the event of a dispute.

The Consumer Financial Protection Bureau on Monday finalized the new rule banning “mandatory arbitration clauses” requiring consumers to forego class-action suits and instead settle disputes in negotiations overseen by arbitrators frequently hired by companies.

The rule immediately ran into fierce opposition by Wall Street and Republicans who control both Congress and the White House. They have long criticized the consumer agency, which is run by a Democrat, Richard Cordray.

Senator Tom Cotton, a member of the Banking Committee, has already announced he is drafting a resolution to kill the rule. His fellow Republican Senator Pat Toomey, chair of the subcommittee on financial institutions and consumer protection, said he is considering a similar step.

Republican lawmakers plan to eliminate the rule, using a law that allows Congress to undo new regulations with simple majority votes in both chambers and a signature from the president.

Analysts and consumer advocates have said the agency’s rule may survive the Congressional challenge. Still, the U.S. Chamber of Commerce is contemplating a legal challenge and Trump administration officials are also looking at ways to kill the rule.

Isaac Boltansky, a policy analyst for the investment firm Compass Point Research & Trading, said the rule has a slightly better than 50 percent chance of surviving in Congress.

Joe Valenti, who tracks the issue for the liberal-leaning Center for American Progress, said the House of Representatives was unified against the rule, which opponents have argued benefits class-action lawyers, not consumers.

“It comes down to the Senate,” said Valenti, noting that the rule would survive if only three Republicans in that chamber switched sides.

That is possible, said Ed Mierzwinksi, the consumer program director for the U.S. Public Interest Research Groups. He noted that Senate Republicans have struggled to gather enough votes for majorities and the calendar is swollen with pressing legislation and confirmation hearings.

In addition, Mierzwinksi said, senators may be leery of appearing to side with Wall Street against consumers. He noted that Wells Fargo & Co used clauses in its account-opening agreements to block customers from suing over its phantom account scandal.

Supporters of the rule say mandatory arbitration denies citizens their day in court and is rigged in favor of big firms. They say litigants banding together in a class-actionlawsuit have a better chance of getting companies to answer publicly for illegal activities and that fears of such a suit can discourage law breaking.

The consumer protection agency wrote the rule after conducting a lengthy, multi-year study of the issue. Opponents of the rule say the study is flawed and that arbitration is cheaper and faster than class-action lawsuits and produces better awards for consumers.

Other Challenges

The Chamber is exploring a prompt legal challenge to the rule, said Matt Webb, senior vice president for its legal reform institute.

Another possible challenge could come from the acting comptroller of the currency, Keith Noreika. He is laying groundwork to invoke an untested provision of the 2010 Dodd-Frank financial reform law that allows the council of the country’s top financial regulators to nullify a consumer agency rule if they decide it threatens the safety and soundness of the banking system.

Rohit Chopra, senior fellow at the Consumer Federation of America and former CFPB assistant director, said a lawsuit will probably fail because the law says the agency can restrict arbitration as long as it hews to its study.

He said the Dodd-Frank provision that the comptroller’s office is looking at was meant to keep risks to the financial system at bay.

“To suggest that this rule would cause a financial crisis is ridiculous on its face,” he said. (Reporting by Pete Schroeder; Editing by Jeffrey Benkoe and David Gregorio)