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The Obama administration was warned as early as March about potential risks with the implementation of HealthCare.gov, according to documents released by the House Energy and Commerce Committee. White House Press Secretary Jay Carney also acknowledged on Tuesday that President Obama was briefed at the time.

Key administration officials at the White House and Department of Health and Human Services received briefings this past spring from McKinsey & Co., a private consulting firm that reviewed more than 200 documents and conducted interviews with HHS staff to identify potential problems before the Oct. 1 rollout.

A report prepared by McKinsey in late March discussed several issues that could hamper the implementation of ObamaCare, including insufficient testing and evolving requirements. The report also warned that the program relied too heavily on outside contractors.

At a hearing held Tuesday by the Energy and Commerce Committee, Chairman Fred Upton, R-Mich., used the report to challenge the accuracy of April testimony by Health and Human Services Secretary Kathleen Sebelius that the site was "on track."

"But we now know that the secretary's testimony did not match what was happening behind the scenes," Upton said, claiming the site was on track "for disaster."

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    Rep. Steve Scalise, R-La., said the reports reveal "chaos in the Obama administration."

    Carney later acknowledged that Obama was briefed as early as March, and said he "absolutely" followed up to see if changes had been made. But he said officials still didn't anticipate the site would perform as poorly as it did.

    In one page of the presentation, the company specifically warned about a "failure to resolve post-launch issues rapidly" -- a scenario that ended up playing out last month. The company cautioned that a "compressed testing window and volume uncertainty," coupled with the fact that response teams were not yet in place, would drag out the process of fixing problems after launch.

    Sebelius, Medicare Chief Marilyn Tavenner, and Gary Cohen, a Medicare and Medicaid oversight official, attended a briefing on the firm’s analysis on April 4, a Capitol Hill source said. Sebelius then testified at an oversight committee hearing two weeks after being briefed on the McKinsey report that the implementation of ObamaCare was on track, according to the Hill source.

    Tim Murphy, R-Pa., a member of the Energy and Commerce Committee, called into question the administration's assurances, arguing that the report suggests the administration was aware the implementation was in trouble months before the fall rollout.

    “Despite assurances from Secretary Sebelius, Marilyn Tavenner, and Gary Cohen that ‘all was well’ and ‘on track’ with the launch of the Affordable Care Act, we now have documents dating back to April that call into question what they told us,” Murphy said.

    White House spokesman Eric Schultz acknowledged late Monday that red flags were raised as the website was being developed and recommendations were taken up by a development team at the Centers for Medicare and Medicaid Services.

    "But nobody anticipated the size and scope of the problems we experienced once the site launched. Since that time, experts have been working night and day to get it functioning – and that is where our focus is, and should be, right now,” Schultz told Fox News in a statement.

    CMS pushed back against the release of the report late Monday, stating that the agency has "continually evaluated progress" and has taken steps to mitigate risks and address concerns with the ObamaCare website rollout.

    "The review was completed six months before the beginning of open enrollment, was in line with industry best practices, and was followed by concrete action to address potential risks—as was intended," the agency said in a statement.

    Fox News' Mike Emanuel contributed to this report.