Martha Johnson, head of the General Services Agency, submitted her resignation to President Obama Monday following reports of excessive spending for a four-day employee training conference, the Washington Post reports.

In her letter of resignation, obtained by the newspaper, the Obama appointee said the Agency made "a significant mis-step."

"Reports of an internal conference in which taxpayer dollars were squandered led me to launch internal reviews, take disciplinary personnel action and institute tough new controls to ensure this incident is not repeated," Johnson wrote. "In addition, I feel I must step aside as Administrator so that the Agency can move forward at this time with a fresh leadership team."

From the Post:

Organizers spent $835,000 on the event, which was attended by 300 employees. The expenses included $147,000 in airfare and lodging at the hotel for six planning trips by a team of organizers. Among the other expenses were $3,200 for a mind reader; $6,300 on commemorative coin set displayed in velvet boxes and $75,000 on a training exercise to build a bicycle.

Additional GSA employees were reportedly also forced out Monday.

Johnson was appointed to her current post by President Obama in April 2009 and Congress confirmed her in Feb. 2010. She previously served as chief of staff of the Agency under President Bill Clinton.

The GSA did not immediately return Yahoo News' requests for comment Monday afternoon.

Update 5:35 p.m. ET: The White House confirmed Johnson's resignation had been received and accepted by the president Monday.

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