Before they left for the talks in Brussels, the union representatives described the decision late last week by the European Commission not to accept the need for tolerances when reading sheep EID tags as making it practically impossible for farmers.
NFUS vice-president Allan Bowie met colleagues from the English NFU, the Irish Farmers Association, the Ulster Framers Union and NFU Cymru to set out their strategy for dealing with this decision.
Speaking after that meeting, he said: "Without tolerances, individual recording in Scotland's extensive sheep systems is simply not possible.
"This hard-line approach to cross-compliance goes against all previous assurances from the commission and would place every sheep farmer in Scotland in a position of non-compliance."
Bowie claimed that Scotland had worked hard since the introduction of this regulation to establish a system that delivered effective traceability, but he wanted the commission to be prepared to implement the regulation in a way that accepted the limitations of current technology.
"Without some flexibility, we will be left with a regulation that, despite their best efforts, the industry cannot comply with and will leave many producers questioning their future when confidence is otherwise quite high."