The shadow Scottish secretary Margaret Curran is visiting Dumfries and Galloway and the Borders today.
With just weeks to go until the independence referendum, the Labour MP will be speaking about the potential effect that having a more formalised border could have on international trade.
The SNP are arguing any negative assertions are based on what they describe as "inaccurate data".
More top news
Our political editor Peter MacMahon looks at the significance of today's meeting between May and Sturgeon
Images released of two men following break-in
Theresa May insists that Brexit must come before Indyref2