Stagecoach, FirstGroup, Go-Ahead and National Express are among 13 firms vying to be the next operators of the Great Western, Thameslink and Essex Thameside rail franchises, Britain's Department of Transport said.

The Government is engaged in the biggest programme of refranchising since the privatisation of the railways, Rail Minister Theresa Villiers said on Thursday, adding that the new operators will be expected to introduce better train services, safer stations and more convenient ways to buy tickets.

Villiers said the new Great Western franchise operator will be involved in improving rail services following completion of the electrification and Intercity Express projects, while the new Thameslink operator will help oversee the completion of the Thameslink project.

The operator of Essex Thameside services will be expected to support economic growth along the Thames Gateway, she added.

FirstGroup was announced as a bidder for all three franchises, National Express and Stagecoach for two, while Go-Ahead was chosen as a bidder for one.

In a separate statement, Go-Ahead welcomed news of being shortlisted to bid for the Thameslink franchise, but said it would seek feedback from the Department for Transport on why it wasn't chosen for the Essex Thameside franchise.

(Reporting by Adveith Nair; Editing by Matt Scuffham)