Mr Hammond said the Hindead Tunnel was one of the missing links in Britain's trunk road network.

BBC: Hindhead Tunnel

As the bridges are part of the motorway and trunk road network, this would be the responsibility of the Welsh government.

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For instance, it provides asphalt and road surfacing services for the Highways Agency trunk road network and it picks up rubble from demolition jobs.

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Most of the money will be spent on easing bottlenecks on the motorways and trunk-road network by widening 360 miles of road, roughly 5% of the total.

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