The Guardian reported Saturday that the bank has set aside $2.9 billion to cover so-called staff costs, including discretionary bonuses, at its investment banking division for the first six months of the year alone.
The newspaper reported that the same RBS division caused a $9.55 billion writedown that wiped out the bank's profits for the same period.
The government had demanded that directors at RBS not receive bonuses this year.
"The government said they would attach strict conditions on bonuses and it is very clear they are doing nothing of the kind," said Vince Cable, the Liberal Democrat Treasury spokesman. "The banks are just making complete monkeys of them."