Aug 28 (Reuters) - Canada's Barrick Gold ABX.TO on Friday said it would challenge an apparent move by the Papua New Guinea government to grant a 20-year lease for the Porgera gold mine to a state-backed firm, the latest escalation in its dispute with Prime Minister James Marape.
Barrick Niugini Ltd, the joint venture that operates Porgera, said in a release it would challenge the "purported grant" of the special mining lease by Marape to state-owned Kumul Minerals Holdings Ltd which it considers "unlawful and "invalid."