On Wednesday Transport Secretary Heidi Alexander is due to announce that the remaining section of the high-speed railway line will no longer be completed in the target time of 2033.
HM Senior Coroner for Lancashire, Dr James Adeley, has written to the Transport Secretary, Heidi Alexander, to say action should be taken to prevent future deaths.
The shocking incident occurred on the Victoria Line during rush hour, with the man bending over and attempting to light up a rock of the drug in full view of fellow passengers.
Plans for a £9 billion road that would pass beneath the River Thames, linking Kent and Essex via a 2.6-mile tunnel, have been formally approved by the transport secretary Heidi Alexander.