The Prime Minister says the entire UK would be worse off if Scotland was to break from the union.
David Cameron was speaking to ITV Border on the second day of the Conservative party conference in Birmingham.
Mr Cameron said he would put party political differences aside to campaign against Scottish independence.
Helen Ford began her interview on the subject of cuts, after the Chancellor announced his intention to save an extra £10 billion from the welfare bill.
She asked the PM if he could understand why some in the North East of England believe they are being unfairly penalised.
Watch Helen's full interview.
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Mainly dry. Light rain out of thicker cloud over hills. Breezy at times and cooler than average
A look ahead at the forecast for the Border region.
Pictures from the commemoration marking the centenary of the Quintinshill rail disaster, which killed more than 200 people, is underway.