The UK minister leading the talks with the Scottish government over post-Brexit powers coming back from Brussels has set his face against separate farm subsidy regimes north and south of the Border.
Damian Green, the First Secretary of State and effectively Theresa May's deputy, warned that farm "subsidy wars" would be "counterproductive" and said there should be a single market across the UK.
In response the Scottish government's 'Brexit minister' Michael Russell argued that the idea there should be a single UK-wide approach to farm support was "not borne out by the current situation".
The latest difference of opinion between the Scottish and UK governments comes against the background of SNP ministers claims of a post-Brexit "power grab" by Westminster.
UK ministers, including Mr Green who has held a series of negotiations with Mr Russell, say that at the end of the talks Holyrood will get substantial new powers currently administered by Brussels.
Mr Green made his comments in an interview with me for last night's Representing Border.
Speaking from the room in the Cabinet Office in Whitehall where the talks were held supported Scottish Secretary David Mundell's claim there would be a post-Brexit "powers bonanza" for Scotland.
But Mr Green was adamant that in terms of farm subsidies, currently set by the EU but administered separately by the Scottish government and the Westminster government, there had to be a level playing field across the UK once Britain has left the EU.
I put it to the First Secretary that this looked like Westminster government will be controlling farming on a UK-wide basis?
So will farm subsidies be determined in Scotland?
But Scotland administers the system now? Mr Green's response:
Commenting on Mr Green's remarks, Michael Russell, the Scottish government minister for UK Negotiations on Scotland’s Place said:
You can see my interview with Damian Green here: