The European Parliament will consider this week whether to follow the United States by bringing in tighter controls on minerals from war zones, but critics say the measures risk being watered down...Leftist MPs and rights groups want the regulation to be compulsory across the board, not just for the 20 smelters and refineries...that would be affected, and are trying to pass amendments to the resolution...They face stiff opposition from right-wing lawmakers and pro-business lobbyists, who are backing the resolution as it is and favour a more voluntary approach to the regulation of conflict minerals...Leading the charge for compulsory regulation is Denis Mukwege,...who last year won Europe's top rights prize for his work treating victims of mass rape...[Refers to Apple and HP]