Trinamool Congress Chief Ms. Mamata Bannerjee is to be sworn-in as the Chief Minister of West Bengal on Friday. She was formally invited by the Governor M.K. Narayanan to form the new government in the state. This follows her election as leader of the Trinamool Congress Legislature party on Monday in the wake of party's spectacular win in the Assembly elections in coalition with Congress. The combine won 220 seats out of 294, routing the Left Front government after 34 years of rule.Talking to reporters later, Ms. Bannerjee said, the Prime Minister had assured her of full support by the Centre. She said that she raised the issue of retaining the Railway Portfolio with the Trinamool Congress but the final decision would be taken by the Prime Minister. Ms. Bannerjee said that she would resign as Railway Minister on Thursday.