Police have confirmed another overspend on the Diplomatic Protection Squad and a review is being carried out.
Last year it was revealed that the squad - which provides security to the Prime Minister and other dignitaries - spent $800,000 more than its budget in the 2009/10 financial year.
A political spat broke out last year when the overspend became known, with the Labour Party accusing Prime Minister John Key of excessively using the DPS, including on holidays overseas.
It later emerged there had been specific threats against Mr Key and a man was arrested and eventually convicted of threatening to kill him.
Police are not yet revealing how much has been overspent this time or when the review will be complete.
Budget blowouts for the squad are not new. In Labour's last three years in government, they ranged from $270,000 to $540,000.