A Pentagon accounting error led the U.S. to overvalue the amount of aid it sent to Ukraine by a whopping $3 billion, Reuters reported Thursday. A senior defense official told Reuters that the Pentagon “discovered inconsistencies in how we value the equipment that we’ve given” to Ukraine and that Congress is being made aware of the adjustment. The official also claimed that it’s possible the real number could end up being higher than $3 billion once the situation is wholly investigated. The error was reportedly caused by overpricing weapons sent to Ukraine from the U.S. stockpile, and could result in additional weaponry being sent as Ukraine defends itself from Russia’s invasion.