The Metropolitan Police are planning to move from Scotland Yard in a bid to save millions of pounds a year.
Deputy Commissioner Craig Mackey told the Mayor's Office for Policing and Crime that the forces could save around £6.5m a year by moving to a smaller office.
The decision comes as the police force looks to make cuts of more than £500m.
Five police stations in London will also be scrapped as part of the cuts: South Norwood, Richmond, Highbury Vale, Walthamstow and Willesden Green.
The number of senior police officers will also fall - but Met bosses stressed that there will still be around 25,000 constables in the capital.
Mr Mackey said the New Scotland Yard building in Westminster's Victoria Street needed £50m worth of refurbishment, but would become an "expensive luxury" as the force made the staff cuts.
"It's an expensive building to run and it's an expensive building to maintain and as we go through this change programme, it's going to have space in it that we don't need. In central London that's an expensive luxury."
The building has been used by the Met since 1967 but costs around £11m per year to run.
The Chairman of the Metropolitan Police Federation John Tully described the sale as like losing the Crown Jewels.
"An iconic building like New Scotland Yard is going to bite the dust," he said. "The Mayor needs to look at his own office. He sits in a brand new building on the South Bank - why doesn't he sell that to save money?
"Thousands of people work at New Scotland Yard and it seems to me that there will be a lot of incremental costs to relocate people."
Some 61 police counter services - smaller desk operations - will also be shut.
Assistant Commissioner for territorial policing Simon Byrne said: "Going forward with the financial pressures we face, it can't make economic sense to keep a building open on the off-chance that someone might pop in a couple of times per week.
Mr Byrne told City Hall that the force could look at co-locating with the fire service and local authorities, as well as manning "pop-up" desks in supermarkets.
Once a move is approved, the force is expected to vacate Scotland Yard within two years.