The GMB union is warning recruitment agencies not to provide Asda with temporary staff as cover during a possible strike by its members.
The GMB is balloting staff at 21 of the supermarket’s distribution centres for strike action in a dispute over union recognition.
A union spokeswoman said it was writing to job agencies to remind them that it is illegal to provide workers to replace striking staff. But Asda said it had no intention of using temps in the event of any strikes.
“The union is trying to fuddle the issue,” a spokesman for Asda said.
“The fact of the matter is that we use agency staff every single day of the year at our depots to cover everything from staff leave to big surges in demand, such as the current World Cup.”
The GMB spokeswoman said the law against employment agencies providing workers to replace striking staff was covered by the Conduct of Employment Agencies and Employment Business Regulations 2003 Act, which came into force in 2004.
The union said it has 7,000 members at Asda’s distribution centres, but the supermarket claims the figure is closer to 4,500.
If GMB members vote in favour of strike action, a walkout is expected in two weeks time.