Government plans to potentially block the ultra-low emission zone expansion coming into force across the whole of London next week have been shelved, it was reported.

Cabinet ministers are said to have been exploring using a little-known legal power allowing them to overrule London mayor Sadiq Khan's plans where they are inconsistent with national policies.

But Government lawyers have apparently said the challenge would fail in the courts, The Telegraph reported.

It means the controversial roll-out - which will see motorists with the highest-polluting vehicles pay £12.50 day levy across the entire capital - will go ahead as planned on Tuesday next week.

The little-known legal clause in the 1999 Greater London Authority Act states that a transport secretary can effectively block a decision from the London Mayor if it is 'inconsistent with national properties relating to transport' and if this would be 'detrimental' to anywhere outside Greater London.

Cabinet ministers are said to have been exploring using a little-known legal power allowing them to overrule London mayor Sadiq Khan 's plans

But given the UK's own policies on improving air pollution and cutting carbon emissions, lawyers have warned the government the move would likely be quashed in court if challenged.

A Downing Street source told the paper: 'We have and continue to look at options, but they are limited. The people who could stop this tomorrow are the Labour Mayor Sadiq Khan.'

Transport for London (TfL) yesterday said motorists who drive non-compliant vehicles across the expanded Ulez network may initially get warning letters to drivers instead of a penalty charge.

Meanwhile, a YouGov poll of 1,000 Londoners shows Mr Khan currently has a popularity rating of minus 12 across the city, with 52 per cent of respondents viewing him unfavourably, compared with 40 per cent favourably.

Yet in outer boroughs, his net rating plunged to minus 24.

It is the latest indication of suburban Londoners rejecting the mayor's Ulez expansion, to take place on August 29, following Labour's disastrous failure to win the Uxbridge by-election from the Tories in West London last month.

The result caused party leader Sir Keir Starmer to ask Mr Khan to 'reflect' on the controversial policy.

But figures from Transport for London say that just one in ten cars will be affected by the expansion.

Nevertheless some desperate motorists have taken to vandalising new Ulez cameras in a bid to save some cash.

The Ulez is set to be expanded to cover all 32 London boroughs on 29 August 2023

Some opponents have resorted to vandalism, with a video showing activists from a group calling itself 'the Blade Runners' sabotaging a ULEZ camera with a tree lopper as diners watched on

It comes as Londoners fear they could soon be subject to other new charges around the city.

It emerged this week that a £2-5 toll will soon be charged at the Blackwall tunnel, depending on the size of vehicle driven.

The toll for the Blackwall Tunnel will only be implemented once the Silvertown Tunnel, which will link Silvertown and Greenwich, opens in 2025.

Some have also raised the prospect of a new £3 toll to use the Hammersmith bridge, which has been closed since 2019 due to cracks appearing in its structure.

Hammersmith & Fulham Council have been clear that the purpose of a potential charge on the bridge would be to raise revenue to repay the costs of repair works on the bridge, and not to deliver wider transport policy objectives,' they said.

'As such, the appropriate approach to introduce the toll is through a tolling order, which would be managed by the Department for Transport.

'The Mayor and TfL are committed to supporting the reopening of Hammersmith Bridge and will continue to work closely with the local council and the Government.'

And in June 2020, Mr Khan rose the Congestion Charge by 30 per cent to £15 after claiming he had been forced to do so under the terms of a £1.6billion government bailout for Transport for London.

Yet a year later there was fury from motoring groups when it emerged the rise had been made permanent.