Scottish farmers have been robbed of £160m in EU convergence payments by the UK Government, Rural Affairs Secretary Fergus Ewing has told the SNP conference.
The extra payments are allocated by the EU to farmers earning less per hectare than the European average.
Mr Ewing said the convergence payments are overwhelmingly aimed at Scottish farmers but are allocated to the UK for redistribution as the member state – and have not been passed on.
He said: “This money was entirely for our farmers, because they earn least per hectare, but it has been taken.
“Theft – it’s a very British institutionalised and legal form of theft.
“They paid us 16% and the rest was snatched, pilfered, robbed.”
Speaking later at a National Farmers Union (NFU) Scotland fringe, Mr Ewing said he had raised the issue repeatedly with Michael Gove, his UK counterpart, but was told it was too late.
He said: “Michael Gove has repeatedly said it will be difficult to unscramble a cake.
“This is legalised theft and I will continue to demand that money back.
“If we can’t get money we’re due from the past then how do we expect to get a fair deal in future?”
NFU Scotland policy director Johnny Hall said he has also written to Mr Gove.
He said: “We have written directly to Mr Gove about this and it is the latest in a series of correspondence.
“We will keep pressing on it – it is not only the Scottish Government pressing the charge, we are pressing as hard as we can too.”
Mr Hall also out his organisation’s preferred options on how agriculture should be run following Brexit, with the Scottish Government taking over the reins from the UK Government Department for Environment, Food & Rural Affairs (Defra).
He said: “We clearly see the rationale for a UK-wide framework for animal health, welfare and standards – that’s essential.
“Thereafter how we channel money into the agricultural sector should be 100% within the gift of the Scottish Government working with Scottish stakeholders. We must have that situation.
“Any notion of a Defra-centric, one-size-fits-all situation is a non-starter.”
Defra Secretary Michael Gove said he wanted to “do right” by farmers but declined to offer to make any payment.
He said: “I understand why people feel the way they do, but the decision having been taken in the way it was makes it difficult to unpick.
“One of the things that I want to do is to ensure that in the future we do right by Scottish farmers.
“However, it is very difficult to unscramble the omelette.”