A major programme to invest millions of pounds in providing new trams and replacing worn-out track on the Metrolink network has moved a step closer.

Greater Manchester Passenger Transport Executive (GMPTE) has named the four companies selected to submit a formal bid to provide eight new trams.

The additional vehicles will help to tackle overcrowding in peak periods and improve the reliability and performance of services.

Another five companies will submit formal bids to replace track on the Bury-Altrincham line which is more than 50 years old in some places and was used by trains until Metrolink took over the route in 1992.

It is anticipated that the successful bidders will be appointed by spring and that the track will be in place by autumn 2007. The new trams are expected to begin operating from autumn 2008.

GMPTE's deputy director general, Geoff Inskip, said: "The eight new trams and track replacement will massively improve Metrolink so that passengers are able to enjoy the benefits of a smoother, quieter and more reliable service.

"The bidding process to appoint contractors, following the Government's decision in July to agree a £102 million package for Metrolink improvements, is well under way."

Alstom Transport, AnsaldoBreda SpA-Firema Trasporti SpA, Bombardier Transportation UK and Siemens Transportation Systems will bid for the contract to supply new trams.

AMEC SPIE Rail (UK) Ltd, Balfour Beatty Rail Projects Limited, Carillion Construction Limited, First Engineering Limited and Mowlem plc will bid for the contract to replace worn-out track.

Nine companies have been selected to submit formal bids for two additional contracts to operate and maintain the Metrolink vehicles and to maintain the network and implement station and stop improvements.

The £102 million funding will buy new trams, ticket machines, stop improvements and track replacement. A total of £44 million will come from GMPTE with the rest being funded from the £520 million announced by the Secretary of State for Transport in 2004.