MILAN, Jan 8 (Reuters) - A group of Telecom Italia (TIM) (TLIT.MI) directors, including representatives of top investor Vivendi (VIV.PA), asked the group"s chairman to call a special board meeting to appoint a new chief executive, two sources close to the matter said. Hit by a string of profit warnings last year, the former phone monopoly lost its fourth CEO in six years after Luigi Gubitosi stepped down in November, a week after receiving a 33 billion euro ($37 billion) takeover approach by U.S. fund KKR (KKR.N). Since then, the CEO powers have been split between the head of TIM Brasil, Pietro Labriola, who has been named general manager, and TIM Chairman Salvatore Rossi. The group has an ordinary board meeting scheduled for Jan. 26. Labriola is a leading candidate for the role of CEO and has the backing of Vivendi, sources have previously said. read more The French group, which controls a 23.8% stake in TIM, gave a cold response to the KKR offer, saying it is too low. A power struggle inside TIM has delayed the group"s response to KKR, which requested access to company data before making a formal bid. Labriola, a veteran TIM executive, has been tasked to iron out a new three-year business plan to revamp TIM on a standalone basis, under a strategy that could include a spin-off of its prized fixed network infrastructure, sources have said. read more Telecom Italia and Vivendi declined to comment. ($1 = 0.8804 euros)