Patil, who was agriculture minister in the erstwhile Prithviraj Chavan Ministry, was nominated as the CLP leader by party chief Sonia Gandhi.
Gandhi was earlier authorized by the CLP to decide its leader.
The announcement by AICC General Secretary Mohan Prakash came as the first session of the Maharashtra Assembly commenced on Monday. The Devendra Fadnavis Government will be seeking trust vote in coming days.
Patil hails from sugar-rich Ahmednagar district and has been a legislator for long. He was also a minister during the Shiv Sena-BJP govt some 20 years back.
He is the son of Balasaheb Vikhe Patil, who had been a minister in the Vajpayee government and had earlier been a Congress MP for several terms.
Congress has been reduced to 42 in the 288-member House in Maharashtra after 15 years in power, leading a coalition along with Sharad Pawar's NCP. It is the third largest party after BJP and Shiv Sena and has just one seat more that estranged ally NCP.
The name of another Maharashtra leader Balasaheb Thorat, who too hails from Ahmednagar district, was also doing the rounds for the post of CLP leader.

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