Thousands of striking platinum mineworkers Thursday marched on the seat of South African government to deliver their grievances to the office of President Jacob Zuma. Leaders of the Association of Mineworkers and Construction Union (AMCU), whose members stopped work six-weeks ago, accuse the government of colluding with  platinum firms to try and break the strike. AMCU Secretary General Jeff Mphahlele, one of the leaders who led the march, said a memorandum was handed to a representative from  Zuma's office in Pretoria. The union gave Zuma two weeks to respond to their demands. "We had already anticipated that the president won't be there to receive us, but we are not too disappointed," said Mphahlele. On Wednesday, talks aimed at ending the strike at top global producers, Anglo American Platinum, Impala Platinum and Lonmin fell apart, after the companies rejected a revised wage demand by the union. AMCU had softened its stance, saying its demand of a minimum wage increase of $1,125 (820 euro) be spread over four years. The union's demand was at the centre of the 2012 deadly strike at Lonmin, when police killed 34 mineworkers on August 16, 2012. Government mediators said Wednesday they had "decided to adjourn the process to give all parties an opportunity to reflect on their respective positions". The world's biggest producer, Amplats, said it was losing 4,000 ounces of platinum a day due to the work stoppage or 100 million rand ($9.3 million). The platinum industry has been hit by intermitted strikes over wages since 2011, in a country that holds around 80 percent of the world's known platinum reserves.