Metropolitan Police Commissioner Dame Cressida Dick has written to all police officers who have retired over the last five years, asking them to return to the force to help enforce new social distancing measures intended to tackle the spread of coronavirus.
The force has also asked officers who are nearing retirement to consider continuing their duties to see out the pandemic.
Dame Cressida said: "Demands on us will grow and vary over the coming weeks but I want people to know and see that the Met is here for them".
Any police constables or sergeants who do agree to return can do so on a full-time or part-time basis. Senior officers may be able to resume their duties if they can contribute specialised skills or experience.
In the case of officers who reached the rank of inspector or higher, Dame Cressida has asked them to consider signing up as special constables and resuming duty for a minimum of 16 hours a month, or taking up the option of volunteering in other roles.
Any former personnel who do wish to sign-up must complete an online form and receive a sponsor from an officer who is currently serving in the force.
The Met said it was waiting for "confirmation that the added costs" of bringing back ex-personnel "will be met by the government".
Dame Cressida added: "Police officers overwhelmingly join 'the job' to help people and to make a difference, and that desire will be as strong today as it was the very first day they joined.
"I am hopeful that these exceptionally experienced and knowledgeable former colleagues choose to come and be part of our team and support London at this extraordinary time."
