Transport chiefs have defended a "ghost bus" which runs once a week from Ealing Broadway to Wandsworth Road - but does not stop for any passengers.

Every Tuesday - at 9.45am precisely - the 50-seat executive coach draws up at a bus stop F outside Ealing Broadway station in west London.

No one ever get on and it departs, empty, on a 70-minute trip to Wandsworth where it waits for two hours before returning, again carrying no passengers.

This mysterious phenomenon occurs when a section of railway track becomes unuseable and a replacement bus service has to be implemented to cater for passenger needs.

Rather than follow the lengthy and expensive public consultation procedure to shut down a railway line or station, which is a legal requirement, the Government instead keeps a bus service running that costs a fraction of the price.

Anthony Smith, of rail watchdog Passenger Focus, said: “There may be situations where the wider passenger benefit justifies changing services to the detriment of some. This should be done with an open, honest, transparent consultation process.”

The “ghost bus”, funded by the Department for Transport (DfT), is not advertised on any timetables or departures screens, and staff at the stations it serves are not even aware it exists.

It costs £500 a day to run and allows the Government to escape the embarrassment of admitting that it has closed several sections of railway to passenger trains in west London.

By running a weekly bus, ministers can claim that a service still operates and avoid the legal requirement to hold a public consultation.

Rail passenger groups fear that the secret Ealing to Wandsworth service sets a dangerous precedent for more closures by stealth.

Until December 14 last year, Crosscountry ran two trains a day between Birmingham and Brighton via Ealing Broadway and sections of track in west London.

A number of passengers regularly used the trains, but the DfT decided the carriages were needed elswewhere to ease overcrowding.

A spokesman for the DfT said: "Consultation revealed a lack of demand on this line and for now a reduced replacement service will serve those passengers who still want to travel on this route.

"We are continuing to monitor this line and are currently looking at the best way of meeting passenger demand which may result in more regular local rail services."