Growers have shunned a Scottish government proposal for a 'Scotland-specific' seed potato agreement with the European Union.
The proposal was part of a consultation which looked at the issue of seed potato exports - a vital Scottish export - to the EU and Northern Ireland.
UK and EU talks continue on equivalence measures for seed potatoes, but it remains very unlikely that any seed potatoes will be exported into the bloc this season.
The Scottish government said the country's seed potato farmers faced an estimated £11 million worth of losses due to a lack of equivalence between the UK and EU.
But NFU Scotland said it was 'categorical in its response' to a Scotland-specific agreement with the EU, saying it was 'not a valuable use of resources across governments or of benefit to the sector'.
The union added that the proposal would be against the UK Internal Market Act 2020, a bill that ensures goods are traded without restrictions throughout the UK.
Its principal response to the consultation was for government to secure an agreement under the EU-UK Trade and Cooperation Agreement (TCA) as soon as possible.
Martin Kennedy, NFU Scotland president said seed potato growers were being severely impacted by the continued blocking of the UK’s application for equivalency.
“There has to be parity for the sector. The current derogation that allows EU seed potatoes to come into the UK until the end of June 2021 has been unhelpful in encouraging an agreement on equivalence and we are calling for this not to be extended."
Mr Kennedy said the union was also advocating government support for identifying and developing a thriving, sustainable market within Britain.
"Seed potato producers are seeking such opportunities and security so that they can grow with confidence knowing that there is a identified market for their high-quality produce.
“NFU Scotland will continue to lobby both governments with urgency to safeguard Scotland’s high-value potato industry," he said.