JEFFERSON CITY, Mo. (AP) — Former Gov. Jay Nixon spent millions of dollars more on his office than what lawmakers budgeted and used taxpayer dollars for personal food and security costs, according to a report by Missouri Democratic Auditor Nicole Galloway's office released Monday.

The audit claims Nixon, a Democrat who was replaced by Republican Gov. Eric Greitens in January, effectively exceeded lawmaker-approved spending on his office, mansion and security by at least $2.2 million in fiscal years 2015 and 2016.

He did so by delaying paying bills and shifting expenses to other agencies, such as splitting the cost of travel on state planes with the Department of Economic Development, according to the closeout audit on Nixon.

Shifting costs to other state agencies "makes it difficult to establish accountability for the true and accurate costs of operating the Governor's office," the audit says. "This practice limits accountability and transparency over certain Governor's office expenditures and distorts the operating costs of both the Governor's office and the state agencies paying the Governor's expenses."

In a response included in the audit, former deputy chief of staff Nick Heberle said the office "accounted for its operational costs in a manner that properly reflected the nature of the work it performed."

The audit notes flights paid for by the Department of Economic Development were for economic development announcements or meetings. Many flights also included other unrelated announcements and meetings, and economic development officials often didn't fly with the governor.

Nixon and his former chief of staff Chris Pieper didn't immediately respond to requests for additional comment from The Associated Press on Monday.

Nixon isn't the first governor to face criticism for taking money from other agencies, although Galloway's audit said the practice increased under Nixon.

The outgoing audit of former Republican Gov. Matt Blunt, who served from 2005 until Nixon took over in 2009, cited Blunt for more than $20,000 in telecommunications, printing and postage charges incurred from January 2008 to April 2008 by the governor's office that was paid for by the Office of Administration's budget in order to prevent the governor's office from exceeding its own budget.

The audit also says Nixon used state funding for transportation and security during personal and political events, as well as for personal food for himself and his family.

Galloway's office notes that state laws are "ambiguous and contradictory" about whether that's allowed. While state law permits the Missouri Highway Patrol to provide transportation and security for the governor, the Missouri Constitution bans the use of state resources for personal or private benefit.

Nixon's office "followed state laws regarding use of state resources consistent with previous governors," according to a response from Nixon's former staffer, who also noted that the governor "is on duty at all times."

The audit recommended that the governor's office push for legislation to clarify how spending can be used and to stop using state funds for personal uses, with the possible exception of security, until that occurs.

Current Republican Gov. Eric Greitens' office didn't comment to the auditor's office about the findings, and spokesman Parker Briden didn't immediately return AP requests for comment Monday.

Other issues cited in the audit include the number of expired or vacant gubernatorial appointment positions during Nixon's time in office and costly hotel and flight expenses for staffers.