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.
More top news
A couple from Newport have decorated their house and garden with thousands of lights to raise money for local charities
Take your waterproofs with you if you're heading out tonight! It's about to turn wet with mist and hill fog by the early hours!
Ian Paul Mcguigan and two men from Liverpool were caught after a police surveillance operation.