Birmingham City Council has climbed down over its desire to see a city-centre metro line run underground and is now backing the previously agreed streetlevel option.

The news came as a major infrastructure study criticised the West Midlands for dragging its heels on transport projects.

Last night, one of the authors of the Institution of Civil Engineers' (ICE) annual "State of The Nation" report said the council's study into the possibility of an underground system was a waste of time.

The Conservative-Lib-Dem administration agreed to fund a consultants' study into tunnelling options 13 months ago.

However, the report, which cost over £300,000 of taxpayers' money, recommends largely the same future surface lines and tunnelling options as had been agreed by the previous Labour administration.

The major difference is a change of priorities, with a desire to see the Airport/NEC line brought forward next.

The report looks at two tunnelling options, at a combined cost of £2 billion, but only one would have a chance of meeting the Government's cost-benefit funding criteria in the forseeable future.

Yesterday, Birmingham City Council leader Mike Whitby (Con Harborne) described talk of delays as a "red herring" and said the work done had " accelerated the process".

He added: "If we had the funding and if the Government wanted to fund a total underground system I would say it is desirable to be underground, but the reality is the Government sets its criteria and we want to move forward with the metro."

The ICE West Midlands Report 2005, which is published today, states that without quick political decisions on public transport, the region will continue to decline.

Terry Mulroy, a member of the ICE and co-author of the West Midlands report, said: "Any transport professional could have told them these conclusions before they started."