A politician has raised concerns about the upcoming Ultra Low Emissions Zone over fears the impact has not been addressed.

The ULEZ is being expanded to the North and South Circular Roads in October 2021, and introduced into central London in April 2019.

During Mayor’s Question Time yesterday, Conservative assembly member Gareth Bacon asked Mayor of London, Sadiq Khan, whether he is satisfied that the impact of the ULEZ being expanded outer London had been fully assessed.

Mr Khan defended his decision to expand the ULEZ – despite recent controversy.

The measure will see Chingford residents pay £12.50 to drive to their local hospital, Whipps Cross in Leytonstone, on the other side of the North Circular Road.

He said: “The issues of clean air and the health of Londoners is a national crisis and I will take action against this.

“The central ULEZ will transform the lives of millions of Londoners.”

But, Mr Bacon continued to press the mayor about the logistics of enforcing the ULEZ system to the North and South Circular Roads rather than just inner London.

The ULEZ will form a protected area in which most vehicles will need to meet exhaust emission standards or pay a daily charge and Mr Bacon wanted to know exactly how vehicle exhaust emissions would be measured in the outer London zones.

Mr Khan admitted that the zone won’t be enforced to outer London until 2021 because of the time it would take to install the infrastructure needed to measure exhaust emissions of cars in outer London.

He said: “One of the reasons we won’t be enforcing the ULEZ to outer London in 2019 is because we don’t currently have the infrastructure, more work is required by Transport for London (TfL).

Mr Khan also added that TfL would probably be using cameras to look at whether cars meet exhaust emission standards as well as working with the Driver and Vehicle Licensing Agency (DVLA) to register cars which did not meet those standards.

But Mr Bacon seemed unsatisfied with the response, saying: “If someone is living within the zone and their vehicle does not meet emission standards but they don’t use their car how will you know?

“There are 3.1 million Londoners are living within that zone.”

The Conservative assembly member also raised concerns that the cost of expanding the ULEZ to outer London had not been properly calculated and thought that they Mayor “seemed to have been underestimated” this cost.

Mr Khan said it was expected to cost £90 to £130 million and promised to provide the breakdown of where exactly the money would be spent at a later date- something he could not answer at the time.

Mr Bacon’s colleague, Keith Prince was also quick to join the debate on Twitter, adding: “Responding to Gareth Bacon’s questions on how his ULEZ scheme would actually work, Sadiq Khan is floundering. He seemed to have no idea about the costs of enforcement or how an expanded ULEZ might actually work.”