Dairy farmers are becoming increasingly confident the multiples will support a rise in milk prices to reflect the cost of production increases.

Tesco was waiting for accurate cost increase figures to come through from Robert Wiseman before making a decision, said Farmers For Action boss David Handley. It had already been supplied figures by the National Farmers' Union and the Royal Association of British Dairy Farmers. Others retailers were expected to follow suit.

Nervousness about the OFT's imminent publication of its investigation into retail price initiatives has made Tesco "ultra-cautious" and ask for figures directly from its suppliers. It has also prompted the dairy industry to approach their customers individually, said Tom Hind of the NFU.

However, Handley said the OFT had assured him that it was not concerned about price rises that would cover genuine increases in the cost of production.

The Arla Foods Milk Partnership was pushing for "substantially more than 1ppl", according to its chairman Jonathan Ovens. Dairy Crest Direct said it was looking for a similar amount.

Prices have risen between 1.5 and 2ppl over the past two years because of oil, feed and fertiliser price rises. The average cost of production is now 21.3ppl.

But market forces alone were unlikely to justify a milk price rise, said industry sources. Indeed, Wiseman confirmed it was to hold the cream price element of its milk price until May, despite deterioration in returns from cream in recent months. These were equivalent to 0.42ppl in January, it said.

Supermarket fresh liquid milk price rises would be a boost for farmers supplying Wiseman, Arla and Dairy Crest farmers on a liquid contract. It would not be good for farmers supplying companies reliant on doorstep milk deliveries, the UHT long-life milk sector and the cheese market.