At least 145,000 South African municipal workers will walk off the job on Monday in a strike aimed at shutting down services including rubbish collection, in the latest dispute to disrupt Africa's biggest economy. 'Our demand of an 18% increase across the board, or R2 000, whichever is greater, is very necessary to meet the economic hardships that municipal workers suffer,' the South African Municipal Workers' Union said in its strike pamphlet.