Passengers on the busiest rush hour trains into Birmingham could be priced back into their cars in an effort to manage overcrowding without new investment.

Rail bosses admit the move, which could see morning peak fares rise by 20 per cent over five years, risks deepening the city's road congestion crisis.

In one of its last acts before being wound up this year, the Strategic Rail Authority today publishes its strategy for making optimum use of West Midlands trains and tracks in the currently barren financial climate.

The Route Utilisation Strategy - the biggest shakeup of the West Midlands railways since privatisation - has been broadly welcomed by the region's transport officials, although proposals to introduce peak fare increases have been criticised as "retrograde".

The SRA believes the proposed fare structure might persuade passengers to spread out the morning rush hour into Birmingham, which at the moment tends to reach a busy peak during a comparatively narrow period of time.

There is also unease about the general thrust of the strategy which identifies "lightly used" regional routes to be sacrificed in order to bolster Birmingham services - including introducing longer trains on the region's busiest line, the Cross City between Lichfield and Longbridge.

Major cuts, or even the complete axeing, of services on the lines between Walsall and Wolverhampton, Stoke-on-Trent and Stafford, Birmingham, Rugeley and Stafford, and Stafford and Nuneaton have been proposed.

The RUS, which will now be considered by the relevant bodies in a 12-week consultation period, aims to:

* make better use of existing rolling stock

* introduce longer peak time trains

* extend off-peak services from Birmingham to provide more services to Kidderminster and Stratford-upon-Avon

* make improvements on the Shrewsbury - Wolverhampton-Birmingham corridor

* possibly introduce a peaktime Shrewsbury to London service

SRA chairman David Quarmby said: "Inevitably there are winners and losers in reallocating use of track and trains but we aim to make the losers few and the winners many."

He added: "The railways in the West Midlands are the crossroads at the centre of the national rail network."

Coun Gary Clarke (Con Walsall Streetly), chairman of the policy-setting West Midlands Passenger Transport Authority, said the mooted 'pricing-off' of demand was contrary to Government policy.

"Reducing rail congestion by pricing passengers off the train and back into their cars would be a very retrograde step. We need investment to increase total capacity and provide an integrated transport network.

"The strategy document acknowledges this would increase road traffic congestion - so it is unacceptable to us and also difficult to see how it squares with Government policy for integrated transport

"Simply taking traffic away from one mode of transport and transferring it to another will not provide the answer the West Midlands needs."