The Crown Estate, the state body which owns both sides of Regent Street along with large tracts of the most exclusive parts of central London, has employed consultants WS Atkins to draw up the proposals, which are currently the subject of the talks with Westminster.
The Crown Estate is particularly keen on the idea of reintroducing trams, which disappeared from the capital's landscape 40 years ago, but has stressed that any such moves could be some way off.
The results of the proposals, likely to cost several million pounds to implement, are expected to be unveiled in a report this autumn following consultations with the relevant authorities. The initial idea is to introduce a number of traffic calming measures over the next year, such as widening the pavements, increasing the number of pedestrian crossings and reducing the number of buses, leading to an eventual aim of drastically reducing or excluding private cars from the street.
Premises affected would include some of the best-known shops in London, such as Hamleys, the toy shop, the department store Liberty and Austin Reed, the outfitters, along with the Cafe Royal.
Christopher Howes, the Crown Estate's chief executive, said the "traffic calming" ideas are an extension of the pounds 4m refurbishment programme of Regent Street undertaken eight years ago.
"That was merely a step towards something really very visionary for Regent Street. What we are in discussions with the Highway Authority, the police and Westminster about is a hierarchy of measures ranging from virtually complete pedestrianisation, long term, starting with limited traffic calming measures," he said. As well as wider pavements, this could involve pollution- free cars or trams to ferry shoppers from one end of the street to the other.
Regent Street, home of London's Christmas lights, could also have a new lighting scheme which would illuminate not only the road but the buildings as well.
Mr Howes said officials would look at how "essential" it was for motorists to use thestreet, although they realised the sensitivity of the issue, given the lack of easy alternative routes. The plans emerged as the Crown Estate announced an 8.8 per cent rise in its revenue surplus - the equivalent of profits - to a record pounds 103m for the year to March.