Potato prices have seen significant market gains in recent months as farmers have kept hold of stocks.
Since the start of 2016, average weekly prices have risen about £20/tonne. For the week to March 11, average prices were £172.94/t and the GB weekly free buy average was £171.81/t.
The prices are a contrast to the start of last year when free buy values were well below £100/t.
Arthur Marshall, from AHDB Potatoes, said the rising prices were prompting farmers to hold potato supplies, causing further tightening in the market.
"There are a number of things affecting the market," he said. "There are reports growers are reluctant to sell and open the stores."
Mr Marshall said this factor was compounding already low stock levels. Figures for the end of January showed the lowest level since the 2012-13 season.
"It comes back to the start of this season. [Last season] there were record yields but area was 8 per cent down," Mr Marshall added.
Discussing the outlook going forward, Mr Marshall suggested there may be a focus on quality.
"We have mixed reports about quality in-store and that could affect the amount the market lifts. We are getting the sense some buyers are prepared to accept a lesser quality supply."