The company said customers would feel "no effect" by action

More than 600 members of the GMB union at the distribution centre in Washington backed strike action.

The ballot was held after a pay offer of 7.75% over two years was rejected.

A union spokesman said the first strike could take place on 27 July. A spokesman for Asda said customers would not "notice a thing."

GMB organiser Michael Hopper said workers at the Ambient Distribution Centre were among the lowest paid in the sector.

Asda has also recently issued "at risk of redundancy" notices to 315 staff at the depot, which deals with tinned and packet foods.

Mr Hopper said: "Obviously this is a sad day that workers are having to vote for action, but our members are adamant that it is necessary.

'Above inflation'

"They have also voted for a ban on continuous overtime in the face of them having the threat of redundancy hanging over them - they are determined to stick together."

Mr Hopper said an initial offer of a 10% pay rise was rejected, because it was on the condition that union members would have to give up collective bargaining rights.

Ed Watson, spokesman for Asda, said: "We're disappointed, but have put contingency plans in place and customers won't notice a thing.

"The offer that was made was a great one and well above the rate of inflation.