White House press secretary Jay Carney speaks to reporters about the so-called "sequester" at the White House in Washington February 28, 2013. (Credit: REUTERS/Kevin Lamarque) White House press secretary Jay Carney speaks to reporters about the so-called "sequester" at the White House in Washington February 28, 2013. (Credit: REUTERS/Kevin Lamarque)

Senior White House officials, including Chief of Staff Denis McDonough, learned last month about a review by the Treasury Department’s inspector general into whether the Internal Revenue Service targeted conservative groups seeking tax-exempt status, but they did not inform President Obama, the White House said Monday.

The acknowledgement is the White House's latest disclosure in a piecemeal, sometimes confusing release of details concerning the extent to which White House officials knew of the IG’s findings that IRS officials engaged in the “inappropriate” targeting of conservative non-profits for heightened scrutiny. Previously, the White House said counsel Kathryn Ruemmler did not learn about the final results of the investigation until the week of April 22nd, and had not disclosed that McDonough and other aides had also been told about the investigation. On Monday, White House Spokesman Jay Carney said a member of Ruemmler's staff learned of the probe the week of April 16; Ruemmler learned of the investigation on April 24th; and after that point she informed the chief of staff and other aides about the probe's findings.

The White House has said President Obama did not learn of the IRS’s actions until he saw news reports on the matter earlier this month.

In a series of TV appearances on Sunday, White House senior adviser Dan Pfeiffer said the White House did not know the details of the investigation or its conclusion until it was released publicly last week, he said.

“It’s important to know what we actually knew, which is just that there was an investigation, it was coming to conclusion,” Pfeiffer said on ABC News’s “This Week With George Stephanopoulos. “Not that we knew the results. We didn’t see the report until it was released last Wednesday.”

Carney emphasized Monday that at the point the White House counsel's first learned about the IG report it remained unfinished and “the publication date of the report was uncertain but likely soon.”

“While we had an indication of the likely findings, until the IG finalizes his report, the findings and conclusions are subject to change. And in fact, many IG reports do change significantly before they are published,” Carney said. “So to be clear, we knew the subject of the investigation and we knew the nature of some of the potential findings, but we did not have a copy of the draft report, we did not know the details, the scope or the motivation surrounding the misconduct, and we did not know who was responsible. Most importantly, the report was not final and still very much subject to change.”

On Monday, Sens. Max Baucus (D-Mont.) and Orrin G. Hatch (R-Utah), who lead the Finance Committee, wrote to Steven T. Miller specifically requesting “documents relating to communications between any and all IRS employees and any and all White House employees, including but not limited to, the President, regarding the targeting of organizations” seeking tax exempt status. The senators also want to see “any written communication, memos, policy drafts, or other documents” related to the IRS’s consideration of tax-exempt status since 2009.

Miller, who resigned last week at the request of President Obama, told the House Ways and Means Committee last week that “foolish mistakes” and “horrible customer service” led IRS employees to single out conservative groups seeking tax-exempt status for special scrutiny.

Under almost four hours of intense questioning, Miller said he had recently met with Treasury officials to discuss how the agency had targeted tax-exempt groups, but insisted that he never had contact with White House officials.

“Absolutely not,” Miller said under questioning by Rep. Devin Nunes (R-Calif.).

Miller is set to testify Tuesday before the Senate Judiciary Committee alongside his predecessor, former IRS Comnmissioner Daniel Shulman, and J. Russell George, the Treasury inspector general for tax administration who wrote the audit report detailing how IRS employees improperly targeted certain groups.

On Wednesday, Shulman and George are set to testify before the House Oversight and Government Reform Committee, alongside Treasury Deputy Secretary Neal Wolin. George told the Ways and Means Committee last Friday that he first informed Wolin about his audit during a meeting last summer.