Sir Bernard was initially appointed to the role in September 2011 and earlier this year had his contract extended until September 2017.
The firm had accused the Mayor of discriminating against its drivers by introducing new rules on mini cab drivers’ ability to speak and understand English and changes to insurance requirements.
The guards, which are already used by 18 police forces, cover a detainee’s face making it impossible to bite officers and thereby substantially reducing the risk of infection with hepatitis and other diseases.
As Chair of the Public Accounts Committee, Dame Margaret repeatedly made headlines for her robust scrutiny of ministers, civil servants and senior business figures.
Earlier this month London Mayor Sadiq Khan approved a review of the cost effectiveness and return on investment generated by London & Partners, the secretive, taxpayer funded company set up by Boris Johnson to promote the capital.
Mr Khan has previously spoken of the need to protect London’s night life and is currently assessing applications from candidates hoping to become his new ‘Night Tsar’.
Government officials have undermined suggestions that setting up a new pension for the Mayor and members of the London Assembly would flout Parliament’s will.
During the regular Mayor’s Question Time session, Green Party assembly member Caroline Russell asked the Mayor for assurances that the amount of money spent on cycling would not decrease over the course of his term.
Historically all decisions to adjust fares levels are taken by the Mayor after being advised on their feasibility and impact on investment in the transport network.