Diplomacy: Theory and Practice, 6th ed.  –  Online updating pages

Chapter 15: Special Missions

p. 253, first bullet point, intelligence officers qualified by virtue of prior diplomatic experience: An outstanding example in the early 2020s is William J. Burns, appointed Director of the CIA by US President Joe Biden in March 2021. He had previously been a career diplomat for 32 years and holder of senior positions in the Department of State and National Security Council; from 2005 until 2008 he had been ambassador to Russia, following which he was made a Career Ambassador, the highest rank in the US Foreign Service. He speaks Russian, French, and Arabic. Among the special missions he is known to have undertaken as Director of the CIA (some secret at the time) are: Kabul, August 2021; Moscow, November 2021; Saudi Arabia, April 2022; Armenia, July 2022; Ankara, November 2022 (where he again met his Russian counterpart, SVR chief Sergei Naryshkin); China, May 2023; and Qatar, November 2023.
second bullet point, and top of following page: A Mossad team, led initially by its chief, David Barnea, was given responsibility for the Israeli negotiations with Hamas on the release of hostages mediated by Qatar in November/December 2023.

Further Reading

Axios, ‘Scoop: Mossad chief visits Qatar for talks on hostages held by Hamas in Gaza’, 30 October 2023

Draper, Robert, ‘William Burns, a C.I.A. Spymaster with Unusal Powers’, The New York Times, 10 May 2023

Faulconbridge, Guy, and Caleb Davis, ‘Kremlin says U.S.-Russian spy chief meeting would make sense’, Reuters, 17 January, 2023

Middle East Eye, ‘CIA chief met with Saudi crown prince on secret trip, says report’, 3 May 2022

Ravid, Barak, ‘CIA chief met Israeli, Qatari officials for new hostage deal talks’, Axios, 18 December 2023

Reuters, ‘Russian spy chief meets Armenian PM days after CIA chief Burns did’, July 19, 2022

Reuters, ‘Russian spy chief confirms call to CIA director after Wagner revolt’, The Guardian, 13 July 2023

Reuters, ‘Mossad, CIA chiefs meet Qatar PM in Doha on Gaza hostage deal’, 9 November 2023

RFE/RL, ‘On Rare Visit to Moscow, CIA’s Burns Holds Talks With SVR Chief Naryshkin’3 November 2021

Sabbagh, Dan and Lorenzo Tondo, ‘CIA director meets Russian counterpart as US denies secret peace talks’, The Guardian, 14 November 2022

Sevastopulo, Demetri, ‘CIA chief made secret trip to China in bid to thaw relations’, Financial Times, 2 June 2023

William J. Burns (diplomat), Wikipedia