London mayor Boris Johnson has been accused of dragging his heels over the Piccadilly line upgrade because he's too obsessed with his own plans for an estuary airport.
Work to improve the ageing line, by providing new trains and a better signalling system, was originally due to be completed this year.
However, Transport for London (TfL) has told the council the upgrade is now not expected to begin until 2019, and won't be completed until the early 2020s.
Passengers at Turnham Green must wait until the work is complete before Piccadilly line trains stop at the station during the day, as Mr Johnson last year confirmed would happen.
Hounslow Council today urged the mayor to ensure improvements are made sooner and questioned whether the delay was connected to his plans for a new Thames estuary airport, which would mean the closure of Heathrow.
Councillor Ed Mayne, the council's cabinet member for community safety and regulation, said: "The Piccadilly line urgently needs an upgrade. But it looks as though it's not as much of a priority for Boris as his own grandiose plans for an estuary airport, which most sensible policy makers and industry experts know won't even take off from the drawing board."
The original completion date of 2014 was deferred in 2010 due to government spending cuts. However, the following year, TfL still estimated work would begin in 2014 and be finished by 2021.