Retail NI chief executive Glyn Roberts said Truss had been shown written evidence of how Northern Ireland independent food retailers had found English suppliers felt unable to continue supplying them.
Roberts told TalkinRetail.com: “It helped put a human face on the situation and simplified the issue to some degree.
“But my take-away was that negotiations are really progressing now. I think we will have a deal before too long.”
Truss was shown a number of e-mail exchanges between independent retailers in Northern Ireland and their suppliers in the rest of the UK that indicated how difficult trading had become.
Several cases showed that UK suppliers felt unable to continue servicing Northern Ireland retailers.
Roberts said: “It is vital this issue needs to be resolved to ensure consumers are given the full product range in Northern Ireland.
“We need a long-term sustainable deal that ensures stability, certainty and affordability for the broader business community in Northern Ireland.”