The chief executive of MTN's South African unit has resigned, citing personal reasons, an internal statement by Africa's largest mobile operator showed on Monday. Ahmad Farroukh took up the post last year and steps down as a strike by 2,000 workers at MTN approaches a second month. Business Times on Sunday reported that Mr Farroukh had announced his resignation plans at a meeting last month but that his proposal had not been officially accepted.Asked to comment on the newspaper report‚ the company would neither confirm nor deny the resignation at the time...