Boris Johnson's transformation from slightly crumpled, portly mop-top to a trimmer, close-cropped prime ministerial candidate has attracted much talk in recent months.

Much of the make-over has been credited to his new girlfriend Carrie Symonds, a PR specialist who has helped him get the right clothes and haircut to succeed in number 10.

However it has been revealed that the spur to tame his golden mane might have been a bargain £15 haircut in his constituency.

The Uxbridge MP, rumoured to earn as much as £750,000 a year, was visiting businesses in his west London seat when he popped in to the Funky Barber in Eastcote.

Staff at the hairdresser's shop nestled between an Indian take-way and a tanning salon on a suburban shopping arcade were bemused when he came in to say hello.

Nick Mazer, 53, who was working in the shop when he came in in November, said the likely next prime minister 'was fascinated, just watching people get a haircut'.

But the barber with 30 years experience - eight of them at the shop - was about to get his hands on the most famous tousled mop in UK politics.

'On his way out my boss Simon shouted: “Boris you need a hair cut'',' he said.

'He started laughing and left – but then he came back and said: “Do you know what – you look like you know what you’re doing I trust you.'''

And so Mr Mazer set to work - and took a bit of a liberty with the famously unkempt barnet.

Nick Mazer getting to grips with Mr Johnson's blond locks at the Funky Barber in Eastcote, in the politician's constituency

The hair salon is nestled between an Indian takeaway and a tanning salon in suburban west London

From slapdash to flash! Mr Johnson was known for his floppy hairstyle and somewhat 'slapdash' appearance. Pictured, the politician out for a run in October 2016

Mr Johnson posed for a selfie with Nick Mazer after his bargain trim - which one of his aides had to pay for

'I always thought he’d look better with shorter hair,' the barber told MailOnline.

Carrie Symonds leaves Boris Johnson's Conservative party leadership campaign in central London last week

'But he was very specific, he said “don’t take too much off this is my look!”

'I thought to myself, this is my big opportunity to make him look a bit smarter.

'I took a couple of inches of all the way round. He has very fine hair – no sign of any hair dye.

'But don’t be fooled by his messy ‘do – it is a definitely styled to look like that. I used a little bit of wax after to give him his look.

'He actually didn’t say much when I had finished but everyone around him loved it.'

He added: 'I obviously inspired his regular barber as he has gone even shorter now.'

As nowhere is safe from Brexit, it came up during Mr Johnson's time in the chair.

'He did joke about Brexit when he was in the chair. He said to me ''don’t mention the B word!''.

'I did, obviously, I asked him where he’d been on holiday too. But he is an expert at dodging questions.'

The only hiccup came when it was time to part with the money for the haircut. Despite his income, including £275,000 for a weekly newspaper column and £79,000 MP's salary, his wallet was apparently empty.

'I don’t think he expected to have to pay – but my boss said to him that’s £15 please - and he didn’t have any money on him!'

'He asked his crew and one of the ladies reached into her purse and found the £15 – then he asked her to cough up for a fiver tip.'

Makeover: Boris Johnson, 54, debuted a noticeably more polished look as he arrived at the Cancer Research UK fundraiser at the BAFTA headquarters in March, pictured

Lean machine: Boris cuts a much slimmer, smarter figure under the influence of Carrie Symonds. Left: Boris in 2013. Right: In 2019.

Mr Johnson's image has undergone the revamp in the last six months, after his return to the backbenches

He revealed in January that he had lost 12 lbs by quitting alcohol and 'late-night binges of chorizo and cheese'.

He and Ms Symonds, 31, have moved into a £1million home together in south London, although he appears not to have completely abandoned comfort food.

During Sunday's Channel 4 leadership debate, which he declined to take part in, two different fast food deliveries were made the plush flat.