Retailers in Northern Ireland have defended supermarkets' milk pricing policy after protests by farmers over what they get paid for their product.
Farmers staged a blockade at two stores in County Londonderry on Thursday and cleared milk from shelves at an Asda store in County Tyrone on Friday.
Farmers for Action said milk was being sold cheaper than bottled water.
But the Northern Ireland Retail Consortium blamed the fall in milk prices on "global economic trends".
The consortium's director, Aodhán Connolly, said: "The price of water and the price of milk are completely different things.
"What we have to understand here is that it's global economic trends, that are beyond the control of Northern Ireland farmers and Northern Ireland retailers, that are the root cause of the reduced price for milk at the moment."
Mr Connolly told the BBC's Good Morning Ulster programme that the price retailers pay farmers "is not connected to the price they charge customers".
"Individual retailers have decided to cut milk prices and they, not farmers, are paying for the price cuts that are currently being enjoyed by consumers," he added.
Mr Connolly said Northern Ireland retailers buy as little as 10% of milk produced by dairy farms in Northern Ireland, while more than 85% was exported.
He said exporters were being affected by the strength of sterling against the euro; the Russian ban on European Union products, the removal of EU quotas, shrinking markets in China and India and a "huge oversupply" of milk in the UK.
However, Sean McAuley from Farmers for Action told the same programme that supermarkets were selling two litre containers of milk for "less than the price of one litre of water".
"The farmer on the ground is not getting a fair slice of the cake because the corporate influence - the supermarket again - is taking far too big a slice of that."
Agriculture Minister Michelle O'Neill said: "We need a concerted effort at this moment in time from Europe, but in the longer term picture what we need is fairness in the supply chain
"Farmers are the people who are being continually pushed when prices are being driven down - they are entitled to produce, they are entitled to receive a fair price for what they produce and if we don't have fairness in the supply chain, then we're not going to have sustainable farming into the future."
Dairy farmers have warned in recent weeks that the financial losses they are facing will put many in their industry out of business.
Mr McAuley said that message must be communicated to shoppers.
He asked farmers to explain their plight to the public during protests but appealed to them not to prevent people from shopping.
He also called on the EU to assist farmers by raising the intervention price to protect the dairy industry.