Bids for a new rail service to link Sussex to the Midlands and East Anglia are being scrutinised by the Government.

Transport Secretary Alistair Darling will next week start assessing bids for the existing Thameslink network between Brighton and Bedford and the expanded rail franchise, which will include routes to Peterborough and Cambridge.

He has promised to make an announcement as to which rail company has won its bid for the new routes by December 21.

Five experienced rail operators are bidding for the Thameslink and the WAGN routes out of Kings Cross and Moorgate.

It would mean the same rail company would be responsible for running services between Brighton, Luton and Bedford and north London lines to Enfield and Potters Bar, along with routes out to Cambridge and Peterborough. This would enable easier access to parts of east London, where the 2012 Olympics will be centered in and around a new athletics stadium and swimming pool to be built at Stratford.

Although it is not possible at present to run trains directly between Brighton and Cambridge and Peterborough, new lines could be built in the Kings Cross area, to link Thameslink lines to the other lines.

Rail company Thameslink was told earlier this year it had lost the franchise and will have to cease responsibility for the operation of the service by April next year Capitaltrains, a consortium made up of freight operator EWS and DSB, the Danish state rail organisation, is one of the companies bidding.

It promises reduced travelling times, modern trains, and more direct services.

Other companies in the running are the National Express Group, which runs the Gatwick Express, First Group, operators of the First Great West Services out of Paddington, Stagecoach, which runs South West Trains and MTR/John Laing, a consortium bringing together the operators of the Hong Kong Metro and the Chiltern Railways.

The winning bidder will take over for four years from April 2006, with an option to continue to Olympic year 2012 if targets are met.