Michael Dore, 55, was driving Lord Mayor Ian Luder’s £200,000 official Phantom VI when he was stopped by police.
He was breathalysed and his blood was allegedly found to contain 54mg of alcohol per 100ml. The legal limit is 35mg.
Mr Luder was not a passenger in the car at the time of the arrest, although Dore was only a short distance from the Lord Mayor’s historic official residence, Mansion House.
Dore has also been charged with not holding a valid driving licence.
The 6.25-litre Rolls-Royce has been owned by the Lord Mayor’s office since it was bought new in the Eighties.
It is 20ft long, weighs two-and-a-half tons and bears the number plate LM 0. Only 374 were made and the Queen has two in her fleet of cars.
Dore appeared in connection with the alleged offences at the City of London Magistrates’ Court last week and was remanded on bail until next month.
When approached at his £300,000 home in Ashtead, Surrey, Dore said: ‘I am not prepared to talk about this.’
A spokesman for the Lord Mayor’s office said: ‘We cannot comment. This is a matter for the police.’ But a source said that Dore has not been suspended from his post.
