The trade union, Mandate, has served strike notice on the South African embassy for January 10th in pursuit of a claim for union recognition.
It claims to represent the majority of the embassy's nine Irish employees and is seeking recognition to discuss pay and working conditions.
According to Mandate's divisional organiser, Mr Albert Murphy, the embassy has not paid any of the increases due under national pay agreements since 1998. Fifteen years ago the union, then known as IDATU, fought a two-year battle with Dunnes Stores to vindicate its members' right not to handle produce from the former apartheid regime in South Africa.
Mr Murphy said yesterday: "It's ironic that a union whose members fought to support the struggle against apartheid are being treated this way and being denied their basic rights as workers."
The ambassador, Ms Melanie Vorwoerd, a former MP for the African National Congress, issued a brief statement last night that her government had "taken note" of the declared dispute by some of their staff members at the Dublin embassy.
"While the South African government is committed to fair terms and conditions of employment for all employees, it is not in the interest of the South African government or its employees to make any further public statement about this matter." Embassies are the sovereign territory of the state they represent, as Irish employees who have sought union recognition in the past, have learnt to their cost.