Marcus Brauchli, the most senior editor at The Wall Street Journal, is to quit his post just four months after the $5bn (£2.5bn) takeover of the newspaper by Rupert Murdoch's News Corp.
The resignation comes amid newsroom gossip about conflicts between Mr Brauchli and Robert Thomson, the former editor of The Times in the UK, who has been brought in as publisher of the Journal.
Employees have regarded Mr Brauchli, whose official title is managing editor, as a bulwark between them and the new proprietor, and a key figure in maintaining the editorial independence of the paper under News Corp.
Mr Brauchli went out of his way yesterday to insist that Mr Murdoch has not sought to impose a political agenda or to promote his own business interests through the paper, but in a memo to staff he added: "I have come to believe the new owners should have a managing editor of their choosing."
Mr Murdoch's takeover of the Journal was sealed in part by his promise to safeguard its integrity, which is policed by an independent editorial board. That board met yesterday and issued a statement saying it was satisfied there was no issue of editorial interference. It must approve a successor.
Les Hinton, chief executive of Dow Jones, the News Corp division that runs the paper, said Mr Brauchli had "deftly guided the Journal's coverage of every major news event of the past decade and is leaving the paper in a position of great strength". The company said it would "begin a search for Mr Brauchli's replacement immediately", with Mr Thomson taking over on an interim basis. Mr Brauchli is staying on as a consultant to News Corp, and may help to develop a business channel for Star TV, its Asian satellite division.
Mr Murdoch is repositioning the Journal as a direct competitor to The New York Times, both for readers and advertising dollars. In recent weeks, the paper has introduced sports coverage and put a greater emphasis on political news. Mr Brauchli is said to have attempted to find a "middle path" between the paper's old guard and Murdoch's new vision for the paper, and a particular bone of contention is believed to have been the sacking of a number of mid-level editors. Mr Murdoch and Mr Thomson are rumoured to have demanded many such redundancies, to free up resources for more reporting.
Mr Brauchli, 46, formally took over the top job last May, soon after news of News Corp's bid to buy Dow Jones first became public. Mr Murdoch succeeded in acquiring Dow Jones several months later only after an extended campaign to win over the Bancroft family, the company's former controlling shareholders.