A series of 24-hour walkouts have taken place

Negotiations between up to 750 members of shop workers' union Usdaw and management of the supermarket giant were set to be held at the conciliation service Acas.

The workers at the depot in Haydock, Merseyside - which supplies stores across the north of England - have staged a series of 24-hour walkouts in a battle to get an �8-an-hour pay rate, the regional average.

They have rejected an offer of �7.55-an-hour, a �1.80 increase on their current rate.

Usdaw general secretary-elect John Hannett said: "We have always maintained that the key to solving this pay dispute lies in keeping dialogue open with Sainsbury's.

'Competitive offer'

"Usdaw officials and shop stewards have worked hard to reach an amicable settlement. The warehouse workers are only seeking a fair rate of pay."

However, Sainsbury's said its current pay offer is an attractive one for staff.

"We are offering a very competitive performance related package which, compared with competitors, is one of the best in the area," a spokeswoman has said.

"In addition we have given an above inflation pay rise for the last three years."