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June 27 (Reuters) - Activist investor Elliott Investment issued a public letter on Tuesday calling for a new chief executive at utility firm NRG Energy, increasing pressure on incumbent Mauricio Gutierrez.
Shares of NRG rose 2.4% in premarket trading.
Elliott disclosed a more than 13% economic interest in NRG last month, and called for a boardroom overhaul and strategic changes in the company for the second time in six years.
The investor had asked NRG to undertake cost cuts worth $500 million, and pushed for a strategic review to refocus the company on its core business of supplying power.
Elliott said NRG's recent measures including its investor day were "wholly insufficient to remedy a deeply flawed strategy overseen by a leadership team unfit to execute".
NRG did not immediately respond to a Reuters request for comment.
(Reporting by Sourasis Bose in Bengaluru; Editing by Krishna Chandra Eluri)
