A mayor who spent £2.3 million of taxpayers' money imposing a 20mph speed limit across his city has been prosecuted - for speeding.

George Ferguson was caught doing 35mph in a 30mph zone by a mobile speed camera.

Critics slammed the 67-year-old after he installed 13,000 20mph speed limit signs across Bristol for wasting time and money.

The project cost more than £2.3 million of taxpayers' money.

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Bristol mayor George Ferguson, who was instrumental in the introduction of a 20mph zones in the city, has been caught speeding

Mr Ferguson, who normally drives an electric-powered Smart car or uses a bicycle to get about the city, was at the wheel of an official fleet car hired by Bristol City Council.

He has apologised for the 'inexcusable mistake,' which took place in Bristol on January 8, and said he would be paying the £100 fine immediately.

'I am shocked to have just discovered I exceeded the speed limit on the Portway last month,' he said.

'This was an inexcusable mistake on my part on one of the rare occasions when I have had to use a council fleet car.

'I am only too aware of the dangers of exceeding speed limits and commend the Avon and Somerset police for their vigilance.

'It serves as a sharp warning to me and I have blemished an otherwise clean licence and shall be paying the penalty charge willingly from my own pocket.'

Mr Ferguson, who normally drivers an electric powered Smart Car or uses a bicycle, described the speeding as an 'inexcusable mistake' for speeding in the Ford Fiesta

The Independent mayor, known for driving a smart car, said it was a 'stupid miskt

The Independent mayor added: 'That is a stupid mistake. I shall pay the fine and I shall pay in a number of other ways I'm sure.

'I have an unblemished license now it'll have some endorsement on it and of course I personally pay the fine.

'But it was 35mph in a 30mph limit on the Portway I obviously wasn't concentrating. I just apologise.

'It is right that speed limits are there for a good purpose. We should respect them. I do respect them. I made a stupid mistake. I'm sorry.

'I make no excuse at all and I shall pay the fine and in my position I probably pay a lot more in reality.'

A decision has not been made as to whether Mr Ferguson will take three penalty points or go on a speed awareness course, said a council spokesman.

Mr Ferguson was elected in November 2012 and is serving a term of three-and-a-half years, with the next mayoral election in the city in 2016.

Ironically, he was believed to have been returning from a visit to the Bloodhound project - a land vehicle attempting to exceed 1,000 miles per hour - when he was clocked at 5mph over the speed limit in the Ford Fiesta.

Bristol City Council voted to introduce 20mph speed limits following a pilot scheme in July 2012.

Mr Ferguson was a keen advocate of the scheme and imposed a city-wide roll out after taking office.

Every street in the city - excluding dual carriageways and 40mph and 50mph roads - are being considered for the tough speed limit, although some other roads may be included on a local basis.

Mr Ferguson, 67, was behind a scheme to install 13,000 20mph speed limit signs across Bristol

Last month it emerged that 6,204 signs have been installed so far with another 7,160 set to be erected in the near future.

Motoring groups and councillors have criticised the plans as an 'utterly stupid waste of money' as no authority will be routinely enforcing the new limit.

Hugh Bladon of the Alliance of British Drivers, said: 'As far as I'm aware this scheme is a huge waste of money.