£4.5m tram works in Wolverhampton four months behind schedule

Transport authority Centro is undertaking the work, which has been dogged by delays.

It was supposed to finish at the end of November but commuters will be unable to get a tram into the city centre until March at the earliest with chiefs still deciding on the best course of action to finish the project.

The main problem has been the unexpected discovery of an abandoned mine shaft, with staff looking at similar schemes across the globe to come up with a solution.

Tram users currently have to get off at The Royal - which reopened in December as part of the work - and either walk into the city centre or get on a replacement bus service.

Until now Centro bosses have refused to put a timetable on when the work will finally finish.

The new tracks will be designed to give passengers a more comfortable journey, while the main St George's platform in Wolverhampton is being extended.

Centro spokesman Peter Cameron said: "Following extensive investigation and analysis over the festive period our consultants are currently working on a number of design options to tackle the complexities around the upgrade to the Midland Metro tracks between The Royal and St George's.

"One option could potentially see the stop opened sometime in March but the definitive time-scales, as to when in spring the route will re-open, will be dictated by the design which best addresses the extensive old mine workings near The Royal and provides the best safety and longevity for the system as whole.

"The technical issues in this location are particularly challenging and it is crucial that we find the best possible solution."