Watch the full interview with the Prime Minister from tonight's programme.
Mr Cameron confirmed that Wales will host the 2014 Nato Summit, an event that he described as "a great moment for Wales to advertise its modern and economically brilliant face to the world".
He also said that an announcement on devolved powers for Wales will be made on Friday.
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Improvements include new visitor centres, medieval chapel restoration and new interactive displays.
Arriva Trains Wales is set to double capacity on some of the busiest routes into Cardiff, it's been announced.
First Minister Carwyn Jones is in north Wales today to open a new hangar at Hawarden Airport.