Royal Bank of Scotland (RBS) has given thousands of its middle-ranking management bonuses equivalent to 5% of their salary, backdating an increase in benefits to January 2009.

The backdated addition, which is understood to have been included as a cash payment in this month’s salary, are typically used by staff to purchase benefits such as healthcare or a company car.

Even staff who have been made redundant over the past year are in line to receive the payment, which is estimated to cost the bank between £30m and £40m a year.

An RBS spokesperson explained: "In February 2009, we announced fundamental changes to our approach to remuneration, which included the closure of the RBS profit share scheme.

“At the time, in recognition of the fact that it was an integral part of a competitive pay structure, it was agreed with UK Financial Investments Limited (UKFI) that we compensate our junior staff for the loss of this benefit.

“Unite subsequently sought an extension of this compensation to include managerial staff.”

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