As part of his visit to Scotland, David Cameron is due to visit HMS Victorious, a Royal Navy submarine which keeps Trident nuclear missiles continuously at sea.
The Scottish National Party say they would scrap Trident in an independent Scotland.
However, Mr Cameron says it would be 'foolish' to abandon it because of the threat of nuclear attack from North Korea.
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A look ahead at another wintry day.
We're showing some of the best weather photos, after Cumbria and the South of Scotland were hit by heavy snow.
Winter is back with weather warnings in place across the region. Ross has the details: