Narendra Kumar Yadav has stepped down as chairman and managing director (CMD) of Mahanagar Telephone Nigam Limited (MTNL). Yadav, member, services, De­part­­ment of Telecommunications, had been given additional charge as CMD of MTNL in June 2015. P.K. Purwar, director, finance, MTNL, has now been given additional charge as CMD. He had earlier held this position between June 2014 and June 2015.