Bengal Chief Minister Mamata Banerjee has cut ties with her brother, Babun Banerjee, after he expressed displeasure over the Trinamool Congress re-nominating Prasun Banerjee (no relation) to contest the Howrah Lok Sabha seat in the forthcoming general election. "My family and I renounce all relationship with Babun..." the fiery Ms Banerjee was quoted by news agency PTI.