Watford's mayor has said Sadiq Khan can expect to receive a "widespread campaign" against a proposal to charge non London-residents to drive into the capital.

Drivers in Hertfordshire could face a daily charge to travel into Greater London under a plan being drawn up by the city's mayor.

Sadiq Khan has confirmed in a letter to Peter Taylor that he has instructed Transport for London (TfL) to look into the "feasibility" of making motorists who live outside of London pay to travel into the capital and its 32 boroughs amid TfL's "unprecedented financial challenges".

Twenty-three Conservative MP's have already described the mooted Greater London Boundary Charge as "draconian" and now Watford mayor Mr Taylor has issued a statement after receiving a response to a letter he wrote to London's mayor about the "boundary tax".

Mr Taylor said: "This would have a big impact on Watford and other boroughs bordering London who currently see London as a place of opportunity for work and leisure.

"The mayor of London needs to consider just how much people from places like Watford contribute to the London economy."

London mayor Sadiq Khan and Watford mayor Peter Taylor. Credit: PA/Watford Borough Council

London mayor Sadiq Khan and Watford mayor Peter Taylor. Credit: PA/Watford Borough Council

In his response to Mr Taylor's letter, Mr Khan wrote: "I stress that at this time, I have asked TfL to investigate the feasibility of a new Greater London Boundary Charge for non-residents, which would apply only to vehicles registered outside London that are driven into the capital."

Mr Khan said he has initially asked TfL to look at a £3.50 daily charge, which would allow people and businesses based outside London to enter and exit as many times as they need to in a day and only pay once.

If this were to be implemented, it would mean it would cost a driver living in Borehamwood £3.50 to travel to somewhere like Edgware, while the same would apply for a Bushey driver heading into Stanmore, or a Watford driver also crossing the border into Harrow.

This charge would be on top of the Central London congestion charge as well as the expansion of the ULEZ zone.

Pictured is the Stirling Corner roundabout on the A1. One side of the roundabout lies in Borehamwood, Hertfordshire, while the other lies in Barnet, Greater London

Pictured is the Stirling Corner roundabout on the A1. One side of the roundabout lies in Borehamwood, Hertfordshire, while the other lies in Barnet, Greater London

Mr Khan also reiterated in his letter to Watford's mayor why it may be necessary to introduce a new charge to travel into Greater London.

He wrote: "I have been calling on the Government to allow the capital to keep the £500 million raised annually from Vehicle Excise Duty (VED) charged to London-based drivers.

"Despite this money being collected from drivers who live in London, ministers spend this huge sum almost exclusively outside the capital, with Transport for London left to fund maintenance of major roads in Greater London from its fares income.

"I have been clear that unless London is allowed to keep the £500 million a year Londoners pay in VED, other ways of raising this money will be needed to help overcome TfL’s unprecedented financial

challenges and achieve the aims of my transport strategy."

London mayor Sadiq Khan. Credit: PA

London mayor Sadiq Khan. Credit: PA

London's Labour mayor said any proposal to push forward with the Greater London boundary charge would require a full consultation, which TfL has previously said would involve non-Londoners.

The feasibility study is expected to take around six months to complete, and any development of the scheme, consultation, and implementation would take at least two years, Mr Khan said.

Peter Taylor concluded: "He (Sadiq Khan) is using this proposal as a bargaining chip with the government, but it won’t go unnoticed by the people who are at risk of extra charges.

"If this proposal is taken forward to public consultation he can expect a widespread campaign against the proposals from the bordering boroughs and the people who are going to be most affected."