He is the man who sent the now infamous email telling staff to "bring your own booze" to the Downing Street garden on May 20, 2020, but who is Martin Reynolds?
Martin Reynolds has been the Prime Minister's Principal Private Secretary since October 2019. That role is traditionally the head of the Prime Minister's Office in 10 Downing Street and the Prime Minister's former aide Dominic Cummings has said he is "the most senior official in No10."
Prior to this role he was ambassador to Libya.
