Police services will be offered in a Post Office in a trial scheme held as Scotland Yard faces making cuts of £500 million.
Deputy Mayor Stephen Greenhalgh announced today that the Metropolitan Police is in "very early discussions" to set up the pilot, which will be established in six months' time.
He said: "Typically they are staffed by people who are security cleared, are used to taking cash, used to transactions. Some Post Offices also have secure rooms as well.
"What we propose to do at this stage, and we are in very early discussions with the Post Office, is to pilot something, to test something out, and to only expand that if it works.
"But in theory Post Offices could provided a fixed point on the high street, with some branding with the Metropolitan Police Service, where you could potentially bring your lost property, if you need to produce identification, if there's a licence that you need to go to a police station for you could maybe do that in a Post Office. And even very simple crime reporting potentially could be done."
The force plans to sell 200 buildings including the landmark New Scotland Yard as it faces making cuts of £500 million to its £3.6 billion annual budget.
In total 65 front counters are facing closure - the force says that fewer people are visiting police stations in person and these are the least used facilities in the capital.
A public consultation will begin tonight on how Met bosses should deal with the heavy cutbacks.
Proposals outlined today include the movement of 800 detectives from specialist squads out to neighbourhood teams.
Assistant Commissioner Simon Byrne said: "Some of the people in squads, if you're using how we train and accredit, aren't actually detectives, they're just constables who wear jeans and a t-shirt. So their level of training is different to someone who has gone on a course."
There would be more constables under the plans - up from 24,630 now to 25,909 in 2015, but a reduction in senior ranks.
These would go from 37 senior managers and 7,160 supervisors now, down to 26 senior managers and 6,022 supervisors in two years' time.
Deputy Commissioner Craig Mackey said dealing with fewer chances for promotion for the remaining officers was "challenging".
He said: "That's one of the most challenging things internally. In fairness that is part of the whole programme of change. There will be fewer opportunities for promotion in the short term, but in 2015/2016 that will open up again."
Instead of an existing 107 expert units in boroughs, there would be one detective squad in each of the 32 London boroughs dealing with a range of crimes.
Mr Byrne said: "Every crime takes place in a street, a home, it's wedded in a business, it's wedded in a community. At the moment we've got over 107 different squads working in my bit of the Met. It's just inefficient.
"Most of the people that we arrest and deal with are spree offenders. By putting false barriers around how we investigate, we miss a trick."
A consultation session will be held in each London borough about the plans, finishing at the end of February.