Plans to introduce a zero-emission zone (Zez) in central London from 2025 have been shelved by City Hall.
The scheme, which was detailed in the London mayor's 2018 transport strategy, proposed a charge be introduced for all petrol and diesel vehicles.
The existing Ultra Low Emission Zone (Ulez) was expanded to include every borough in London on Tuesday.
City Hall said it would support councils that wished to introduce a Zez within their boroughs.
The proposal laid out in the 2018 strategy was to "implement zero-emission zones in town centres from 2020 and aim to deliver a zero-emission zone in central London from 2025".
The strategy also proposed a zero-emission zone for inner London by 2040 and a London-wide zone by 2050.
The plan states: "As well as incentives and supporting infrastructure to encourage a move to [ultra-low emission vehicles], it will also be necessary to use disincentives to phase out fossil fuel vehicles altogether.
"A zero-emission zone is likely to require vehicles that drive within it - that are not capable of operating with zero-exhaust emissions - to pay road user charges (similar to those in Ulez or Lez)."
A spokesperson for Sadiq Khan told BBC London the mayor was now focused on achieving net-zero emissions in the capital by 2030.
"The mayor is rolling out some of the most ambitious policies of any city in the world to clean up London's air, including the expansion of the Ultra Low Emission Zone, bringing cleaner air to five million more Londoners," the spokesperson said.
Mr Khan said he believed the 2024 mayoral election would not be a referendum on the expansion of Ulez.
BBC London contacted councils in central London to ask if they had plans to introduce zero-emission zones within their boroughs, supported by City Hall.
Camden Council and Kensington and Chelsea London Borough Council said they had no plans in place to implement such an emissions scheme. Westminster, Hackney, Islington, Tower Hamlets, Southwark, Wandsworth and Lambeth councils have not responded.
A Transport for London (TfL) spokesperson said: "Some small-scale trials of zero or ultra-low emission streets have taken place previously in London, with the support of the mayor and TfL.
"We have no plans at present to progress the introduction of new zero-emission zones."
According to a response from the mayor to a question on zero-emission zones published in January, the only such zone put in place was on Beech Street in the City of London.
The "traffic experiment" ran from March 2020 to September 2021 but ended once a temporary traffic order expired, the mayor said.