(Recasts with Conti's resignation, adds company details)
By Elvira Pollina
MILAN, Sept 26 (Reuters) - The chairman of Telecom Italia (TIM), Fulvio Conti, stepped down on Thursday in a move that signals an easing of tensions between the group's main shareholders.
TIM said in a statement that its board will meet on Oct. 21 to discuss the appointment of a successor.
Conti's resignation at a board meeting on Thursday was expected after he said earlier this month he was considering stepping down in light of a "renewed climate of trust" between the company's shareholders.
Vivendi, TIM's biggest investor with a 24% stake, and U.S. activist fund Elliott have been trading blows for more than a year over how to revive TIM, an underperforming business saddled with 25 billion euros ($27.3 billion) of debt.
But relationships between the two have improved in recent months, giving fresh impetus to talks on a series of a long-standing issues - from the creation of a single broadband network with rival Open Fiber to the possible conversion of TIM's savings shares.
Conti was appointed TIM chairman in May 2018 by Elliott, which has a stake of just under 10% and controls two-thirds of the telecom operator's 15-strong board.
He soon became embroiled in a dispute with Vivendi, which accused him of favouring Elliott in a protracted boardroom battle - something he has repeatedly denied.
State lender Cassa Depositi e Prestiti, which also has a stake of around 10% in TIM and favours the single network project, acted as a peacemaker between the two former foes.
TIM said board member Michele Valensise would take on the chairman role on an interim basis.
Two sources close to the matter told Reuters a short list of candidates for the job had been drawn up but no decision has been made yet.
Franco Bassanini, the head of Italian broadband operator Open Fiber, denied on Thursday a press report that he would take the job. Another newspaper, la Repubblica, cited as a front-runner veteran manager Innocenzo Cipolletta but a source close to the matter said his appointment was unlikely. ($1 = 0.9155 euro) (Reporting by Elvira Pollina in Milan Editing by Alexander Smith and Matthew Lewis)