Two House Republicans are asking the White House to explain its “unusual arrangement” with Elizabeth Warren, who President Barack Obama on Friday appointed to a special advisory role to help lead the Consumer Financial Protection Bureau.

Oversight and Government Reform ranking member Darrell Issa (Calif.) and Financial Services ranking member Spencer Bachus (Ala.) sent a letter Friday to White House Counsel Robert Bauer raising questions about Warren being able to bypass the Senate confirmation process given the scope of her job.

Warren’s new post includes responsibilities at the White House and the Treasury Department, which means Obama’s appointment “is undermining Congressional oversight while giving her substantive authority over the CFPB.” They wrote. “This is unprecedented.”

Issa and Bachus called on Bauer to provide information about Warren’s responsibilities, her salary and where she will file financial disclosure statements. They also asked for a pledge to make Warren available for testimony “before all relevant Congressional committees.”

White House spokesman Robert Gibbs said he did not know whether Warren would be made available to testify on Capitol Hill. During a Friday briefing, he defended Obama’s handling of Warren’s appointment and said giving her an advisory position “made perfect sense” since Senate Republicans would have stalled her nomination for months if she were formally nominated as the new agency’s permanent director.

“Anybody that gets nominated, it’s going to take months and months and months before they’re ready to be involved in the standing up of this position. And we know from the appointments process that the Republicans in the Senate have virtually ground to a halt,” Gibbs said.

“What the president was focused on was, how do you get this agency started? How do you get this agency stood up? And this made perfect sense,” he said. “There’s no circumventing of the law in any way on this.”

Gibbs dodged questions about whether Warren is in the running to be the agency’s chief, a post he said Obama is hoping to fill in the “next several months.”