"I have apologised to the Barclays Board, and accepted its conclusion that my personal actions in this matter were errors on my part."
The investigation will focus on Staley's individual conduct and senior manager responsibilities relating to Barclays whistleblowing programme, as well as Barclays' systems and controls and culture relating to whistleblowing.
Barclays said it was first made aware of the matter in early 2017 after an employee raised concerns over the adequacy of Barclays whistleblowing procedures.
The Board instructed an external law firm, Simmons & Simmons LLP, to conduct an investigation into the matter and notified the FCA and PRA.
The investigation by Simmons & Simmons found that Mr Staley "honestly, but mistakenly" believed that it was permissible to identify the author of the letter.
Staley says he was trying to protect a colleague who had experienced personal difficulties in the past from what he believed to be an "unfair personal attack"
However he was informed that it was not appropriate to take steps to identify the author and no further action was taken. Mr Staley later apologised to the Board for his error.
The Board says it will be issuing a formal written reprimand to Staley and has decided that a "very significant compensation adjustment" will be made to his bonus.
The Board is also commissioning independent reviews of Barclays relevant processes and controls, including its whistleblowing programme.
John McFarlane, Barclays Chairman, said: "I am personally very disappointed and apologetic that this situation has occurred, particularly as we strive to operate to the highest possible ethical standards. The Board takes Barclays culture and the integrity of its controls extremely seriously. We have investigated this matter fully using an external law firm and we will be commissioning an independent review of Barclays processes and controls to determine what improvements may be required.
"Taking into account both the circumstances of this matter and his otherwise exemplary record since joining Barclays, including contributing significantly to improvements in Barclays culture and controls, Jes continues to have the Board's unanimous confidence and it will support his re-appointment at Barclays Annual General Meeting on 10 May 2017."
Jes Staley, Group Chief Executive Officer said: "I have apologised to the Barclays Board, and accepted its conclusion that my personal actions in this matter were errors on my part. I will also accept whatever sanction it deems appropriate. I will cooperate fully with the Financial Conduct Authority and the Prudential Regulatory Authority, which are now both examining this matter.
"Our whistleblowing process is one of the most important means by which we protect our culture and values at Barclays and I certainly want to ensure that all colleagues, and others who may utilise it, understand the criticality which I attach to it."
