A random audit of expenses of 12 members of the Oireachtas has led to €16,000 being handed back after it was found that some of the expenses claimed could not be properly accounted for.

The external "sample" audit by the consultancy firm Mazars was for expenses claimed between January to December last year.

According to the Irish Independent, seven of the 12 TDs, ministers and senators who had their expenses audited last year were unable to provide evidence that all of the money was spent correctly.

Fine Gael TD Derek Keating returned the most after it was found that €7,571 worth of his claims were ineligible.

Next was fellow Fine Gael TD Ray Butler, who was unable to provide receipts or documentation to show that more than €4,900 was claimed correctly.

Others who had failed to provide evidence that the money was spent correctly included Labour TD Ciaran Lynch, Fine Gael TD Joe O'Reilly , Labour junior minister Alex White, Fine Gael junior minister Ciaran Cannon and Senator Susan O'Keeffe

TDs can receive €15,000 a year unvouched or up to €25,700 with receipts. Senators can claim €9,250 a year unvouched or up to €15,000 vouched.

In December's Budget, Public Expenditure Minister Brendan Howlin said the unvouched option would be abolished from next year and the amount that politicans could claim would be cut by 10%.