West Bengal Governor CV Ananda Bose, who made headlines over his differences with Chief Minister Mamata Banerjee, has resigned, sources have said. Bose is currently in Delhi. The reason for his resignation -- which comes ahead of the assembly election in the state -- is not known yet. His replacement, Mamata Banerjee claimed, will be RN Ravi, who is currently the Governor of another Opposition-ruled state -- Tamil Nadu.