IRS Commissioner Charles Rettig says his agency "anticipates" responding to congressional requests for President Donald Trump's tax returns amid growing pressure from House Democrats for transparency. During a hearing on the IRS budget before the Senate Finance Committee, Rettig was pressed by Sen. Ron Wyden, Democrat of Oregon, on a request made by House Ways and Means Chairman Richard Neal, Democrat of Massachusetts, who set a deadline of Wednesday for the submission of Mr. Trump's returns.

"We have received the letter, we're working on the letter with counsel, we anticipate to respond," Rettig testified. Neal sent a formal request to the IRS for six years of Mr. Trump's tax returns, arguing the committee "has a responsibility to conduct oversight of our voluntary Federal tax system and determine how Americans — including those elected to our highest office — are complying with those laws."

Wyden went on to ask Rettig if he agreed that an IRS delegation order that the Treasury secretary does not get involved in taxpayer-specific issues means that it is "his job and his alone" to respond to Neal's request to release the returns. Rettig refused to respond in detail, saying only that while he's "aware" of the order, the IRS "is a bureau of the Treasury and is supervised by the Treasury."

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These comments came a day after Treasury Secretary Steven Mnuchin testified before a House subcommittee that it's his department's "intent to follow the law" in responding to the request to release the president's taxes.

Later, asked if anyone in the administration at any time discussed with Rettig whether he would comply with Neal's request, Rettig replied, "No."

Wyden reminded Rettig he had previously testified during his Senate confirmation hearing he would "resist political pressure" and pronounced it "unfortunate" that the commissioner would not firmly say it was his job to respond to Neal's request himself.

"I believe, based no our personal interaction, Senator, that you have a pretty good read on me as a person and I'll leave it at that," Rettig responded to Wyden bluntly. Fellow Democrat Sen. Mark Warner of Virginia echoed Wyden, urging Rettig to respond to the request for the president's tax returns "without any interference by the Treasury Secretary" or the White House.

Under the law, the chairman of the Ways and Means Committee and designated staff are allowed to view the returns but not release them to the public.

Republicans have blasted the Democratic-led effort as tensions between the White House and Congressional Democrats have intensified.