In the memo, Fiorina said Capellas' departure was by mutual agreement, saying that “it is only natural… that as a former CEO, Michael would want to become a CEO again”.
“With Michael's departure, HP's four business groups and worldwide operations will report directly to me. We do not plan to fill the position of president,” she said.
Capellas became president of HP after the company merged with Compaq, where he was CEO, six months ago.
Rumours abound that Capellas is due to take over from John Sidgmore as CEO of embattled US telco WorldCom, but so far neither WorldCom or Capellas have made any comment on such a move.
Capellas will relinquish his title of president at HP and resign from his position on the board on 1 December. Fiorina is expected to resume the title of president, which she held at the pre-merger HP.