The private Tube companies maintaining the London Underground (LU) network have been criticised for not doing enough to improve the system.
Tube Lines and Metronet took over maintenance of the Tube in 2003
LU's managing director Tim O'Toole says Metronet and Tube Lines are not spending enough money on new equipment or doing enough engineering work.
He said the firms, which admit making profits of about £2m a week, are failing passengers.
But Metronet and Tube Lines say they are working well.
A spokesman for Metronet said: "We're now investing more than £1bn a year to improve standards and reliability.
"We understand the impatience of London Underground and of customers - but the PPP set out a clear programme of work - and we are working hard to meet that programme."
Metronet and Tube Lines took over the infrastructure of the Tube in 2003.
The firms have 30-year contracts worth £15bn and combined profits of almost £100m.
Terry Morgan, chief executive, Tube Lines, said: "This time last year we had 100 people on stations. This time around we have well over 1,000. That's not reduction, that is 10 times fold on station work."
Mr O'Toole urged Metronet's and Tube Line's shareholders to prove that the Public Private Partnership (PPP) scheme was working by putting more money into the Tube for maintenance work sooner.
"I do believe they [Metronet and Tube Lines] are working to a plan and meeting goals that they set for themselves.
"But they will make more money if they improve the Tube faster. They will also encourage the public and bring along the government to put more money into this.
"I believe this is a long-term campaign and we need to bring the public with us otherwise we are going to lose their support," he said.
He said the greatest improvements will not happen until 2009.
Further criticism of the Tube firms is expected later this month from the Commons Transport Select Committee.