“At the moment the county is getting absolutely nil. It is in a bubble. We have very few producers on dedicated supply contracts, so they are missing out," said Mr Mandle.
He added: "There seems to be the need to have discussions as to why the extra monies from the Morrisons new milk brand is going to be going to everybody across the board who supply Arla.
"This is not right as every producer is being paid a different amount, with some getting 29ppl, while others only 20ppl. We need to know how much of this money is going to come back into this county."
Mr Mandle also criticised Morrisons for putting the new milk brand alongside its cheaper alternative.
"This is immoral and crazy," he continued. "It's going to be very hard for families on a budget to ignore the lower-priced carton.
"This county is taking all the volatility hitting the milk price."
Morrisons corporate services director Martyn Jones said it recognised that the current market for liquid milk was impacting on hardworking dairy farmers and their families.
"We want to reassure the industry that the retail price we charge for Morrisons milk reflects the highly competitive retail market," he said. "It is not linked to the price we pay our milk suppliers.
"We also want to clarify that our current three-year contract with Arla, who supply the majority of our milk, uses a cost model that automatically adjusts the price that we pay for milk, based on a combination of the independently set farmgate price and other commodities such as diesel and plastics that influence the cost of milk."
Keith Twentyman, NFU, group secretary, also based at Carlisle, said it was a "good" initiative that would put some money back into the struggling dairy industry, but also posed the question of 'how much and how would it be distributed'.
"We do have a sprinkling of Arla producers here in Cumbria," Mr Twentyman said, "but there aren't many liquid producers, the majority are supplying milk that is going into processing cheese.
"So potentially any money handed over to Arla could be going to dairy farmers out of the UK."
A spokesman for Arla confirmed all their European farmer producers would benefit from the milk price promise.
"This is a welcome step by Morrisons, and one which will benefit all our 13,500 suppliers," he added.
NFU dairy board chairman Rob Harrison said he welcomed the Morrisons move, and added that retailers have a big role to play in helping customers to support the UK dairy sector.
Dairy producers in Cumbria have faced a turbulent 12 months with milk prices dropping to they claim well below the cost of production.
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