Richard Moore is to become the new chief of the Secret Intelligence Service (MI6), the Foreign Office has said.
He replaces Sir Alex Younger, who will leave the service in the autumn.
Mr Moore is currently political director in the Foreign and Commonwealth Office and a former ambassador to Turkey.
He previously held director roles in MI6 and has been deputy national security adviser in the Cabinet Office.
He Moore, said: “I am pleased and honoured to be asked to return to lead my service.
“SIS plays a vital role – with MI5 and GCHQ – in keeping the British people safe and promoting UK interests overseas.
“I look forward to continuing that work alongside the brave and dedicated team at SIS.”
Outgoing MI6 chief Sir Alex Younger said: “I am delighted by this appointment. Richard is a highly accomplished intelligence officer and we look forward to welcoming him back to the service.”
Foreign Secretary Dominic Raab said: “I am delighted to appoint Richard as the next chief of the Secret Intelligence Service.
“He returns to SIS with tremendous experience and will oversee the work of a group of men and women whose tireless efforts are rarely seen in public, but which are critical for the security and prosperity of the UK.
“I pay tribute to Sir Alex Younger for everything he has done during his time leading the Secret Intelligence Service. He has carefully and effectively guided the service during a time of increased and more diverse threats.”
