Former chancellor of the Exchequer George Osborne had been appointed editor of the London Evening Standard, its owner Evgeny Lebedev said.
Mr Lebedev wrote on Twitter: "Thrilled to announce the new editor of the Evening Standard is George Osborne.
"I am proud to have an editor of such substance, who reinforces the Standard's standing and influence in London and whose political viewpoint - socially liberal and economically pragmatic - closely matches that of many of our readers.
"George is London through and through and I am confident he is the right person to build on the fantastic legacy of Sarah Sands."
Mr Osborne, the Tory MP for Tatton who was sacked as chancellor by incoming Prime Minister Theresa May last year, replaced the current editor Sarah Sands, who is leaving the Standard after five years to join the BBC.
He will take up his role in early May, editing the paper an average of four days a week.
The newspaper said: "The Standard's schedule will enable Mr Osborne to edit the paper and continue to fulfil his other commitments, including as an MP; giving him the time to vote and contribute in Parliament in the afternoon after the paper has gone to print, and be in his constituency.
"He will edit the paper an average of four days a week."