The National Union of Mineworkers (NUM) said it will back Cyril Ramaphosa to be ANC president after Jacob Zuma. "This is not only based on the tradition of the ANC, but also on the suitability of the candidate," NUM general secretary David Sipunzi said yesterday. "Zuma must serve his [full] term."Ramaphosa co-founded NUM in 1982.Zuma, 74, is scheduled to depart as leader of the ANC next year and as South Africa's president in 2019.The contest to replace Zuma is intensifying as calls mount from ANC veterans, civil rights groups and church officials for him to quit or be fired after he was implicated in a series of scandals. The nation's next leader is expected to emerge from the governing ANC - the party has won every parliamentary vote since the end of apartheid 22 years ago by more than 60%.Ramaphosa helped to negotiate a peaceful end to apartheid and draft South Africa's first democratic constitution. The 63-year-old politician lost out to Thabo Mbeki in the contest to succeed Nelson Mandela as president in 1999 and went into business, amassing a fortune before returning to full-time politics in 2012 when he became ANC deputy president.The NUM has been displaced by the Association of Mineworkers and Construction Union as the biggest representative of employees in the platinum industry.Sipunzi said his union is working very hard to recruit members after numbers declined to 192000 from 206000 in July last year.The union's relationship with Mineral Resources Minister Mosebenzi Zwane is "nonexistent", Sipunzi said. "We are concerned that he does not deem it important to form a relationship with us when we're part of the major stakeholders; instead, he is busy with other things." ..