Simon Calder, a travel journalist, says the disruption at London Paddington train station could continue into the weekend.
A number of services, including trains to and from south Wales, were cancelled after signalling problems caused major disruption to a line.
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Wales Captain Sam Warburton says his team are raring to go as they kick off their Six Nations campaign in Dublin tomorrow.
Liberal Democrat leader Tim Farron has criticised Labour at the party's spring conference in Cardiff.
A Royal Gun Salute was held at Cardiff Castle earlier today to mark the 64th anniversary of the Queen's accession to the throne.