(Adds quote from Fiat chairman, reason for shakeup, 2011 loss)
MILAN, April 4 (Reuters) - The shareholder group that controls Italy's RCS MediaGroup said on Wednesday it will slim down the number of board members at RCS, in a move that is expected to cut shareholder interference and help boost financial performance.
In a statement, the shareholder group said the board will drop from 22 members to 12, adding it had accepted the request of board member Diego Della Valle, the owner of shoe group Tod's , to exit the group.
In the shakeup, Chairman Piergaetano Marchetti will step down, replaced by academic Angelo Provasoli. Chief Executive Antonello Perricone will also leave, people familiar with the situation said.
A new CEO is expected to be named in time for the group's upcoming shareholders' meeting on May 2.
RCS, which publishes Italy's leading daily, Corriere della Sera, posted a 322 million e uro loss in 2011, mainly due to a writedown of an acquisition in Spain.
Like other publishers, the company has struggled in recent years to stem steady losses in advertising revenue as readers increasingly look to the Internet for news.
The boardroom shakeup is unusual for Italy and is particularly surprising at RCS, which counts some of the country's top companies as its shareholders.
The publisher's 22-person board is a holdover from the chummy business atmosphere that used to prevail at the Italian blue-chip club known as "salotto buono."
Two of the group's largest shareholders, Fiat and Mediobanca, were pushing for a clean sweep, slashing the board to 12.
Fiat Chairman John Elkann, who spearheaded the changes, said earlier Wednesday that the move was "indispensable to give the company the governance it needs."
Elkann has gained insight into the publishing industry as chairman and CEO of Exor, an investment company that holds 5 percent of British news magazine The Economist.
Fiat holds 10.5 percent of RCS, and Mediobanca has a 14.2 percent stake.
"The clumsy and spurious behaviour of some of its (board) members in recent days has prompted me to ask determinedly to free my shares from all ties," Della Valle said in a statement.
He said he believed the Corriere della Sera needed to remain independent.
(Reporting By Claudia Cristoferi and Jennifer Clark)