The Welsh Secretary, David Jones, has expressed his pleasure at today's Network Rail announcement.
Mr Jones described a modern rail network in Wales as "crucial" for the growth of the country's economy.
As a regular rail user, I know that the re-signalling of many rail lines across Wales can only be good news for all passengers and I am particularly pleased that the important north-south line links will be some of the first to be upgraded. The Newport to Shrewsbury re-signalling also marks the start of the build programme for electrification of South Wales mainline which we announced last year.
He also welcomed news that the mainline between London and Cardiff will be electrified by 2018.
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