A watchdog to protect farmers and food producers from the questionable practices of supermarkets could still be two years away, Labour has warned.
The Government last year introduced draft legislation to create an adjudicator to investigate alleged breaches of the grocery industry Code of Practice.
But Labour's Shadow Environment Secretary, Mary Creagh, has warned it risks being 2014/15 before an adjudicator is in place to enforce the rules.
The overseer, which would monitor the ten retailers with an annual turnover of more than £1 billion, including Tesco, Asda and Sainsbury's, was first mooted more than a decade ago.
Supermarkets, who claim the new body will force up food prices, have come under fire for demanding one-off payments from suppliers to guarantee future business, forcing them to sell produce on two-for-one discounts and breaking contracts at no notice.
In her address at the annual Oxford Farming Conference, Ms Creagh told delegates: "We want to see a fair and competitive supply chain for growers, processors and retailers.
"That is why Labour in Government got cross-party agreement on the need for a Groceries Code Adjudicator to ensure a fair deal for farmers and producers.
"But we are worried by Government delays which mean that the adjudicator will probably not be up and running until 2014/15."
The legislation is the responsibility of Vince Cable's Department for Business, Innovation and Skills.
Labour has voiced concern that the Department for the Environment, Food and Rural Affairs does not boast the clout to accelerate the process against fierce lobbying from the retail industry.
MPs have questioned whether the adjudicator will be fit for purpose once it completes is passage through Parliament without the power to issue hefty fines. As it stands, its main weapon to ward off bully-boy tactics will be naming and shaming retailers.
A report by the powerful cross-party Business Select Committee of MPs, which proposed various amendments to the Bill, was rejected by the Government.
Farmers and food producers form the backbone of the Westcountry economy, and have called for an effective regulator for years.
Elsewhere in her speech, Ms Creagh hit out at Defra's failure to lead by example by stocking enough British produce in its own canteens.
She said: "The Government has lofty aspirations about 'Buying British' but has failed to deliver on its promises.
"It spends £2 billion a year on food and is well-placed to support British farmers and food standards through procurement.
"Yet Defra's latest figures show that the department bought less than a third of its food from British sources in 2011. That must change."