Unions and passenger watchdogs reacted with "I told you so" today after an independent arbiter criticised the private company contracted to provide most maintenance services on the London Underground.

The Tube regulator, Chris Bolt, assessed Metronet on its performance from April 2003, when it took over maintenance of all Tube lines except for the Jubilee, Northern and Piccadilly under the controversial public-private partnership (PPP) scheme.

He said that the performance of the two Metronet infrastructure companies had improved over the past year, but added: "My conclusion is that neither... has performed in line with the required standard over the period as a whole."

Mr Bolt's 70-page report is his first as the official PPP arbiter and contains detailed assessments of a long list of criteria against agreed benchmarks - rather than listing the actual problems faced by passengers and train operators because of maintenance delays.

But Brian Cooke, chairman of London TravelWatch, a passenger watchdog body, said: "It will be no surprise to the long-suffering Tube passengers that Metronet’s performance is not in line with the required standard.

"After the failures, the inconvenience, the excuses and inaccurate information used by Metronet over the past year, many Londoners will regard that as a huge understatement.

"We hope that Metronet has also learnt that giving misleading information to passengers is not in their interest. Passengers want the truth."

Metronet is split into two companies, Metronet Rail SSL and Metronet Rail BCV. The other three lines are maintained by another "infraco" (infrastructure company) called Tube Lines.

Mr Bolt, who is also head of the Office of Rail Regulation as well as arbiter under the London Underground PPP, said that Metronet was "significantly behind schedule" on its work on Tube stations and there was "poor delivery of maintenance and renewals" on track work.

He said: "While Metronet is demonstrating good performance in some areas, such as fleet management, it needs to make significant improvements in other areas.

"It is particularly important that Metronet should fully implement its asset and risk management programmes and make further improvements in delivery of the track and stations programmes.

"This is essential if Metronet is to improve its overall performance to the standard required in the PPP agreements. I hope to see much clearer evidence of efficiency and economy and of good industry practice at next year’s review."

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