Workers at Burton’s Foods in Blackpool have rejected a 6% pay offer despite union leaders’ endorsement of the deal.

The offer of a 3% pay rise to be followed by another 3% increase in January was thrown out by members of the Bakers, Food and Allied Workers Union on Wednesday night, The Grocer has learned.

A union official suggested that management refusal to include three months of back pay in the offer at the new rate could explain why workers went against its recommendation. The union is sitting down with members today to find out why they rejected the deal. A meeting between the union and management is also planned for Monday, with the aim of negotiating a settlement.

“The company is disappointed by the outcome of the union’s ballot,” said a Burton’s spokesman. “Burton’s Foods and BFAWU representatives both felt the latest offer was a reasonable compromise and it is unfortunate union members voted in favour of rejecting it.”

Staff at the Blackpool ­factory, where Jammie Dodgers, Maryland cookies and Cadbury Fingers are made, have been at loggerheads with management for months trying to hammer out a pay deal.

In July, a strike was averted when Burton’s challenged the validity of a ballot on industrial action. A month earlier, union members had voted to strike ­after rejecting a pay offer. Workers have not received a pay increase since 2009.