South Africa's striking platinum miners Monday rejected calls to end a three-month strike, saying they had not reached an agreement on the latest pay offer. The Association of Mineworkers and Construction Union (AMCU) said talks with their members "have not managed to yield an agreement to date". The union faces increasingly vocal calls to end the strike, which has hit South African exports and threatens to slow already moribund growth rates. "The strike has gone on too long. The strike is not helping workers," President Jacob Zuma said on Monday, in his strongest call for a resolution to date. "I find there's an irresponsibility element here. You can't go on with a strike that at the end makes them lose their jobs." "In any negotiations, you must be ready to give and take. You must be ready to compromise." But AMCU is opposed to an offer of a 12,500 rand ($1,200/ 860 euros) salary package by July 2017,which was extended by top producers Anglo American Platinum, Impala Platinum and Lonmin last month. "Our members in all the three mines resoundingly rejected the current employer offer and reiterated their original demand of 12,500 rand in four years." the union said in a statement. It is calling for a basic wage offer of this amount, excluding benefits like housing and medical allowances. More than 80,000 AMCU union members downed tools on January 23, in what has turned into one of the longest strikes in South Africa's recent history. The workers have not been paid since the strike began. Lonmin, the third top platinum producer, has given the workers until May 8 to accept its latest offer, bypassing the union. But the union expressed "great disdain" at being circumvented, saying such conduct undermined it and its members. "AMCU strike is a protected industrial action and therefore there must be no undue pressure on the parties while they are exercising their constitution rights," it said. The strike has so far cost the workers around 6.4-billion rand in lost income and producers some 14.5 billion rand in revenue according to mining firms. The key industry has been hit by intermittent strikes over wages since 2011, in a country that holds around 80 percent of the world's known platinum reserves.