Our Scotland Political Editor Peter MacMahon spoke to the Prime Minister during his visit to the Scottish Conservative Conference.
Watch the full interview on independence - and how it could affect the border - here:
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Kerrie Gosney brings you Saturday night's forecast
Showers turning heavy with a risk of thunder. Dry and bright start on Sunday, cloudy and wet from the west later
Scotland's First Minister said her government will seek 'immediate discussions' with Brussels to "protect Scotland's place in the EU".