Kosher meat producers have reacted furiously to a study which claimed their prices had soared in the past decade.
Butchers said the figures had been "manipulated" to ignore market forces and increased production costs.
The report by economists Anthony Tricot and Andrea Silberman - published in last week's JC - calculated that kosher meat prices had doubled, while non-kosher prices had risen by 40 per cent.
Jacky Lipowicz, Licensed Kosher Meat Traders' Association chairman, said members had regularly slashed prices because they knew Jewish customers were struggling to afford staples such as chicken.