The Government has rejected an offer from security firm G4S to repay the £24m it owes for overcharging in credit notes.
Officials turned down the settlement and say they will "pursue all possible avenues" to recoup more taxpayers' money.
A Ministry of Justice spokesman said it was still working with the firms and the independent auditors to work out "what the final sum will be".
"The Secretary of State has been clear: we are determined to secure a refund for the taxpayer.
"We have taken appropriate legal advice and will pursue all possible avenues."
More top news
Errors with medication may cause around 1,700 deaths annually in England and contribute to up to 22,000 each year, according to research.
The deputy sheriff stood outside Marjory Douglas Stoneman school, watching the western entrance of the school for more than four minutes.
The day will feel cold, especially along the east coast where there is also a small chance of catching the odd wintry shower.