Team Anna member, Arvind Kejriwal, has slammed home minister P Chidambaram for denying permission for their forum 'India Against Corruption' to stage a fast in Delhi. Kejriwal also questioned the credibility of UPA candidate Pranab Mukherjee for the presidential post. Mukherjee is pitted against PA Sangma, backed by BJP, its allies and other regional opposition parties. Mukherjee has served as finance minister, foreign minister and commerce minister twice and also as Defence Minister in his 43-year-long political career.