Network Rail planned to spend £5 billion on modernising the Great Western Main Line, its South Wales branch and other associated lines. The modernisation plans were announced at separate times but their development time-scales overlap in the 2010s. The work included electrification, resignalling, new rolling stock and station upgrades. According to Network Rail, the modernisation started in June 2010 and was due to end in 2017. As of December 2019, electrification was complete as far west as Cardiff Central, and also from Reading to Newbury.