French nuclear giant Areva said Wednesday its chief operating officer Philippe Knoche would take over as interim chief executive after CEO Luc Oursel stepped down for health reasons.

"The supervisory board has decided to bestow Mr. Philippe Knoche the same powers as those of the chairman of the executive board, until the next general assembly will be held to decide the change in the governance," Areva said in a statement.

This general assembly is due on December 9.

Oursel announced on Monday he was stepping down to seek treatment for unspecified health issues.

Knoche, 45, joined Areva in 2000. He was named chief operating officer in 2009 and in 2011 became a member of the executive board.

The company, which is 87-percent owned by the French state, has suffered in recent years as interest in nuclear power has cooled following the 2011 Fukushima catastrophe in Japan.

Areva announced earlier this month that it would cut investments and step up sales of non-strategic assets as it tries to shore up its finances.