New Scotland Yard is to be sold as the Metropolitan Police faces making cuts of more than £500 million, a senior officer said today.

Deputy Commissioner Craig Mackey told the Mayor's Office for Policing and Crime that the force hopes to save around £6.5 million per year by moving to a smaller headquarters.

Plans to close another five police stations have been approved so far, and there are proposals to shut 61 "front counter" services.

New Scotland Yard has been in its current location in Victoria Street since 1967 but Mr Mackey said it would take an investment of around £50 million to bring the building up to scratch.

He said that, as the force faces staff cuts, there will also be more and more space at the site, which is "an expensive luxury" in central London.

Mr Mackey said: "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 force paid £124.5 million for the building in 2008 and it costs £11 million per year to run.

It is expected that the move will take around two years once approvals are in place.

The five police stations that are to close are South Norwood, Richmond, Highbury Vale, Walthamstow and Willesden Green.

Met bosses are also shutting 61 counter services - some of which only receive a handful of visitors per day.

Assistant Commissioner for territorial policing Simon Byrne said: "There is a great variance across London in terms of the footfall in public counters. Our busiest gets around 100 visitors per day, our quietest on a good day gets two.

"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."

The cost of the counters varies from £70 per visit down to around £10 per visit, he said.

Chairman of the Metropolitan Police Federation John Tully said the sale of New Scotland Yard was like losing the Crown Jewels.

"It's very regrettable that it's come to this. Clearly it's a building of age and it's got upkeep costs, but the old police authority and now Mopac have had a consistent policy of selling off property and they've now reached the Crown Jewels," he said.

"An iconic building like New Scotland Yard is going to bite the dust.

"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."

He said there had already been significant investment to refurbish the building, and the sale would be another knock to officers' morale.

While Met bosses have stressed that, despite the cuts, there will be more constables in the capital than ever - 25,000 - Mr Tully said numbers of more senior ranks will be reduced.

He said: "The Mayor has pledged to maintain numbers at about 32,000 but you balance that against cuts, for example 20% budget cuts, then something has got to give and it's going to be sergeants and above, right to the top.

"We have grave concerns around the supervisory ranks that we represent - sergeant, inspector and chief inspector.

"The people who are left are going to be severely challenged, because, to be frank, some of them can't do all of their job now. There are only so many hours in the day.

"The people who we represent have been working their socks off, especially during the last 18 months, and then they have been told that they've got to do more and better and smarter. It's a bit of a kick in the teeth.

"The pressure is piling on and something will break. Hopefully it won't be at the cost of injury or worse."

As part of the property cutbacks, the force could look at co-locating with the fire service and local authorities, and manning "pop-up" desks in supermarkets, Mr Byrne told a meeting at City Hall this morning.

There is also the possibility of police services being provided in post offices, Deputy Mayor for Policing and Crime Stephen Greenhalgh said.

Mr Mackey added that the force could build on the public spirit shown during the Olympics to encourage volunteers to help the police.