The United Conservative Party says an internal audit of its MLA expenses has uncovered $557.30 in invalid payments that were caused by "administrative errors." 

"All UCP MLAs with anomalies in their expenses have reimbursed the Crown and are taking additional steps to ensure proper due diligence in the future," interim leader Nathan Cooper said in a news release Thursday. 

The caucus will draft recommendations to modernize the expense system and update the rules.

They will bring them to the next meeting of the members services committee on Sept. 14.

The review was prompted by the controversy over expenses claimed by former UCP MLA Derek Fildebrandt. 

The MLA for Strathmore-Brooks resigned from the UCP caucus earlier this week after news broke that he was charged with leaving the scene of a hit and run in June 2016.

Last week, it was revealed Fildebrandt sublet his apartment on Airbnb while collecting an MLA accommodation allowance.

The Alberta Party also flagged expense claims on Monday that suggested the MLA may have claimed the same meals twice.

Fildebrandt said he would pay back his sublet earnings to the government. He said the meal receipts were due to administrative errors and vowed to reimburse any discrepancy.