The Scottish Labour leader Johann Lamont said she would share a platform with David Cameron and the Conservatives, to campaign against independence.
She said she had a "responsibility" to join those with whom she would normally disagree, to save the union.
Lamont also told Representing Border's Peter MacMahon her plans for greater devolution in the event of a no vote.
Watch the full interview below:
Representing Border is ITV Border's new political programme for the South of Scotland, on ITV Freeview on Tuesdays, Wednesdays and Thursdays at 10:35pm. Catch up with the latest episode online by clicking this link.