Four months after buying Dow Jones for $5bn, Rupert Murdoch has cemented his influence over the media group’s flagship Wall Street Journal with the resignation on Tuesday of Marcus Brauchli, the newspaper’s managing editor.

In a letter to staff, Mr Brauchli, who was promoted to the paper’s top editorial job a year ago, cast his departure as another chapter in the takeover by Mr Murdoch’s News Corp. “I am proud to have been part of this exceptionally talented team,” he wrote. “But now that the ownership transition has taken place, I have come to believe that the new owners should have a managing editor of their choice.”

Mr Brauchli added that the new owners had “rigorously” adhered to a code of conduct set up to safeguard the Journal’s editorial integrity following its acquisition by News Corp last year.

He will take up a new post as a consultant to News Corp, focusing on Asia, where he once served as a foreign correspondent. News Corp said a search for his successor would begin immediately. Internal candidates are said to include Nik Deogun, editor of the Journal’s Money & Investing section.

Mr Brauchli’s departure is another sign of Mr Murdoch’s ongoing campaign to shake-up one of the world’s most respected financial newspapers.

The extent of the new owner’s involvement in the paper was visible on Tuesday on its editorial page, which featured a signed piece by Mr Murdoch calling for a free trade deal with Colombia.

Mr Brauchli had tried to tread a middle course between the Journal’s traditionalists and his News Corp bosses, arguing that the conglomerate’s deep pockets could aid the paper at a time of industry transition.

However, that position became untenable as the two sides clashed over the pace of change at the Journal and its editorial direction, according to several people familiar with the matter.

These people said Mr Brauchli objected to efforts to minimise feature articles – its traditional strength – in favour of shorter news stories. Another point of contention was Mr Murdoch’s push to broaden the Journal’s coverage from business to politics and lifestyle issues, in an attempt to claw readers and advertisers from the New York Times.

“This is symbolic of the push from business coverage to politics and it’s symbolic of Murdoch being fully in control,” said one former Dow Jones executive, who called Mr Brauchli “a world-class editor who was hand-picked and groomed as the chosen one at the Journal”.

Mr Brauchli’s power had been curtailed in December when Mr Murdoch appointed Robert Thomson, former editor of News Corp’s Times of London, as the Journal’s new publisher.

Meanwhile, Mr Murdoch pushed forward on another newspaper transaction that would further enhance his power in the New York media market: a deal to buy Newsday from the Tribune Company for about $580m.

The acquisition of the Long Island tabloid would allow Mr Murdoch to consolidate operations with his money-losing New York Post. For Tribune, it would ease the burden of a $650m loan payment coming due in December as a result of the $8.2bn buy-out of the media group led by Sam Zell last year.

Both companies declined to comment on the matter. The proposed deal would require regulatory approval.