Harrods staff are threatening to strike over a pay deal they claim favours non-union workers.
The union Unite is to ballot 275 support workers for the Kinghtsbridge store who were excluded from an extra two days leave entitlement granted to shop floor staff.
According to the union, staff are also angry that they have been offered a below- inflation pay offer of 3.5 per cent.
Richard Munn, a Unite regional official, said: "It is very worrying that those workers who were not given two extra days holidays are in a recognised union, while the shop floor workers who got the extra leave do not have a recognised union.
"Harrods shoppers will be surprised to learn that the "top people's" shop treats its workers in this way."
Staff were told by the store's owner, Mr Al Fayed, over the Harrods loudspeaker that, due to their hard work, staff would get an extra two days leave.
However, staff in the union later learned that their employer had excluded them from this arrangement, Unite claims.
The ballot for industrial action begins on Monday, August 4th, 2008 and close on Monday, August 18th, 2008.