Harrow Council is set to spend up to £400,000 of public money in a legal battle against Mayor of London Sadiq Khan's decision to expand the ultra-low emission zone (ULEZ).

The amount of money at stake is said to be enough to run two libraries for a year, and one Labour critic has said the Harrow Tories should be "ashamed" of the waste.

Yesterday (February 2) four councils, Harrow, Hillingdon, Bexley and Bromley, were faced with a deadline to sign an agreement for the expansion.

But the councils jointly refused to do so.

Instead, they said in defiance: "Bexley, Bromley, Harrow and Hillingdon councils will not sign the Section 8 agreement with TfL while legal advice is being taken.”

Transport for London (TfL) stated in a letter to council leaders that it still has the power to go ahead with the installation of signs and enforcement cameras on the boroughs’ roads.

Despite this, Harrow Council is set to issue High Court proceedings by February 24 against Mr Khan, the Evening Standard has reported.

The council also reportedly said they will fight the case alone if other Tory boroughs back down.

Labour's London Assembly member for Brent and Harrow, Krupesh Hirani, said Harrow Tories should be "ashamed" of wasting almost half a million pounds.

The four grounds for judicial review are that Mr Khan acted beyond his powers, relied upon “incorrect” assumptions, denied private motorists access to a vehicle scrappage scheme, and lacked detail in how the costs and income of the expansion were calculated.

However, Transport for London has stated that none of the grounds established that the decisions were unlawful, or that this is arguable.

Harrow Times: A graphic showing the ULEZ boundary from August 29, 2023A graphic showing the ULEZ boundary from August 29, 2023 (Image: PA/Transport for London)

A TfL spokesperson clarified that while there was a deadline yesterday for the agreement, this does not mean the transport body will immediately begin a forced implementation of additional cameras - this will instead come into force after August 29.

However TfL has confirmed their letter explained that it has the legal powers to override the councils’ refusal, but they would prefer to have their consent.

Had they signed the agreement, the local authorities would have a say over the design and positioning of new cameras and signs.

A TfL spokesperson said: “The Mayor has been clear that with 4,000 Londoners a year dying from toxic air, his decision to expand the ULEZ should be implemented with minimal delay.

“In doing so we are working closely and collaboratively with all boroughs concerned to install the infrastructure needed.”