The Mail & Guardian newspaper announced the resignation of its editor-in-chief, Ferial Haffajee, on Monday.
Haffajee, 42, would become editor-in-chief of City Press in July, said Trevor Ncube, the Mail & Guardian CEO and proprietor, in a statement.
She will replace Khathu Mamaila, current editor of City Press, who has been promoted to general manager of the paper.
Haffajee said she was "devastated" to leave the Mail & Guardian.
"It has been part of my life since I began working as a journalist, but I need a new challenge." she said.
She said she had first joined the M&G in 1991 and while she left on two occasions to work for the SABC and Financial Mail, she always came back.
"It (the M&G) is in my DNA and spirit," she said.
She said she accepted the position at City Press because Media24 made her a "wonderful" offer.
"It is a newspaper I read religiously and enjoy enormously. It is an honour to follow in the footsteps of Mathatha Tsedu and Khathu Mamaila, both of whom have honed a fine medium for the 21st century," she said in a Media24 statement.
"I hope to inject a touch of Afropolitanism into the paper and to bring with me some of the investigative journalism I have learnt at my alma mater, the Mail & Guardian.
"There is a fine team in place and I look forward to working with them and in a company known for its entrepreneurialism and verve," said Haffajee.
Francois Groepe, CEO of Media24, said Haffajee's appointment would see City Press strengthening its "Distinctly African" brand.
"Media24 views these appointments as further strengthening City Press' independent focus on quality journalism and content."
Groepe said Haffajee had distinguished herself in the South African and international arena. "Some of her achievements include Young Global Leader of the World Economic Forum (2008), Media Woman of the Year (2006, The Media magazine) and she is an active member and alumni of the Africa Leadership Institute.
"She is also a former chairperson of the South African National Editors' Forum and serves on the board of the World Editors' Forum."
Mamaila, who has been a journalist for 20 years, completed his MBA at the Gordon Institute of Business Science in Pretoria in 2004.
"The reason I did the MBA was to prepare myself for this, but I did not think it would happen so soon," he said.
Ncube said Haffajee was the third editor the Mail & Guardian had grown for the industry in the past five years, after Mondli Makhanya, now editor-in-chief of the Sunday Times and Fikile Moya (former sports editor of the newspaper), now editor of the Sowetan.
"This is testimony to the formidable learning curve we provide at M&G media," said Ncube, adding he would announce a successor to Haffajee in a fortnight.
"Naturally I am disappointed by Ferial's departure but she leaves with my full blessings," said Ncube. - Sapa