By David Willey
BBC News, Rome
Pope Benedict XVI has chosen a close former colleague to become his new Vatican secretary of state.
Cardinal Bertone (l) replaces a fellow Italian, Cardinal Sodano
Italian cardinal Tarcisio Bertone, 71, will replace fellow Italian Angelo Sodano as the Pope's number two.
Cardinal Bertone, currently archbishop of Genoa, has long been a trusted collaborator of Benedict. They used to work in the same Vatican department.
It is the second senior appointment made by the Pope from among his closest former departmental colleagues.
Last year, the Pope chose an American cardinal, William Levada, to take over his own former Vatican job.
The Vatican secretary of state is the Pope's official deputy, but has no powers to make declarations relating to faith and dogma - he is simply the Vatican's senior administrator.
The new appointment confirms Pope Benedict's extremely cautious attitude towards replacing church leaders chosen by his predecessor John Paul II.
The only reason why Cardinal Sodano is leaving is that he is already three years past the Vatican's official retirement age of 75.