'We look like clowns': Boris Johnson faces calls to step in as furious Tories accuse ministers of giving Sadiq Khan 'free run' to blame government for London congestion charge extension - even though he has been handed billions of pounds

Boris Johnson is facing calls to step in as Tories vent fury that the government is being made to look like 'clowns' by Sadiq Khan in the row over funding for London.

The PM has been warned that the mayor is being given free run to blame them for deeply unpopular ideas like extending the congestion charge. 

A briefing war has been gathering pace between City Hall and the government over the latest round of Covid bailout negotiations for Transport for London, against the backdrop of mayoral elections in May.

Mr Khan is demanding £4.9billion to cover the next 18 months after fare revenues went through the floor due to lockdown, and says Transport Secretary Grant Shapps is trying to attach conditions including stretching the £15 Congestion Charge Zone to the North and South Circular roads in 12 months' time.

But Tory MPs are increasingly livid that Mr Shapps is bungling the negotiations and allowing Mr Khan to put his side of the argument across to the public unchallenged. 

Boris Johnson is facing calls to step in as Tories vent fury that the government is being made to look like 'clowns' by Sadiq Khan (pictured left week) in the row over funding for London

The PM (pictured on Friday) has been warned that the mayor is being given free run to blame them for deeply unpopular ideas like extending the congestion charge

Mr Khan has been accusing ministers of demanding an extension of the congestion zone to the North and South circulars in return for a TfL bailout

They insist the Labour mayor - who is battling Conservative candidate Shaun Bailey for re-election - has pushed TfL to the brink of collapse with profligate policies and is now trying to avoid having to introduce unpopular measures to balance the books.

London MPs have had two calls with Mr Shapps recently in which they read him the riot act over the situation. 

But Mr Shapps and No10 transport chief Andrew Gilligan apparently pointed the finger at civil servants, saying they were leading the talks. 

'Khan has completely outplayed us on this and Grant's team need to get a grip,' one senior Tory source told MailOnline.

'A lot of colleagues feel like they've been lied to and all Grant and Gilligan do is blame civil servants. 

'Many have gone on record denying Khan's claims and now look like clowns. It's beyond incompetent from Shapps.' 

Another senior Conservative told the Observer MPs would not tolerate the government being implicated in extending the congestion charge. 'If this was even suggested, then there'd be real complaints and blood on the walls,' they said.

A Tory MP said: 'Khan has now been allowed to basically hide problems of his own making behind Covid. 

'We're letting him get away with blaming everything on the government.'

The tensions surfaced at PMQs in the Commons last week, when MPs urged Mr Johnson to confirm Mr Khan was not being forced to extend the congestion charge zone.

Mr Johnson, himself a former London mayor, said Mr Khan's policies had left a 'massive black hole' and action to balance the books would be 'entirely his responsibility'.

But he risked inflaming the situation by stopping short of completely ruling out forcing Mr Khan into a congestion charge hike. 

Tory MPs are increasingly livid that Mr Shapps (pictured last week) is bungling the negotiations and allowing Mr Khan to put his side of the argument across to the public unchallenged

The London mayor says he needs a £4.9bn settlement to bail out TfL for the next 18 months after passenger numbers collapsed and revenue crumbled as a result of the pandemic

'Any need to make up that deficit is entirely down to him, it is entirely his responsibility,' Mr Johnson said.

'Any expansion of the congestion charge or any other measure taken to improve the finances of TfL are entirely the responsibility of the bankrupt current Labour Mayor of London.'  

A two-week package has been agreed by the government to give more time for negotiations. 

Mr Khan's team has warned TfL could effectively go bankrupt if funding is not provided soon. 

In theory, it could only operate the Woolwich ferry and some school bus services.