The managing director of Newtork Rail's network operations told the Today programme that any attempt to upgrade existing lines, rather than implement the HS2, would inevitably lead to "very heavy disruption" to services.
Spending £20 billion on upgrading the existing network isn't an alternative. The disruption that would be caused would be a nightmare. This report makes that absolutely clear.
It would only give us a third of the additional capacity which would mean that we would not be able to put more freight on the rail, we would not be able to put additional services into intermediate stations.
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Armed police have carried out a raid apparently linked to Wednesday's deadly terror attack in Westminster.
Cheryl Grimmer vanished from inside a beach shower block in Wollongong, Australia, in 1970, when she was just three.
Pc Keith Palmer was on the front line and because of his actions, the Westminster attacker was unable to kill anyone else.