(Reuters) -Activist investor Elliott Investment Management is increasing pressure on NRG Energy and seeking to oust its CEO Mauricio Gutierrez, the Wall Street Journal reported on Wednesday, citing people familiar with the matter.

Elliott is in talks with potential candidates to replace the U.S. power company's CEO as well as other top executives, the report said.

In a statement to Reuters, an NRG spokesperson said that the company's board "fully supports NRG's CEO Mauricio Gutierrez and management team," adding that the company will be discussing its strategic plan with shareholders at its investor day.

Elliott Investment did not immediately respond to Reuters' request for comment.

The report comes after Elliott sent a letter to NRG's board last month, pushing for a boardroom overhaul. The activist investor had urged the company to conduct a review of its home services strategy and add new independent directors.

Elliott had disclosed a more than 13% economic interest in the utility company in May, which it said was worth around $1 billion, without specifying how much, if any, of that interest was in NRG stock.

(Reporting by Rahat Sandhu in Bengaluru; additional reporting by Rishabh Jaiswal; Editing by Krishna Chandra Eluri, Maju Samuel and Subhranshu Sahu)