A former special adviser to Peter Mandelson has been appointed new director of Downing Street's strategic communications unit.
Mr Wegg-Prosser was ex-aide to Peter Mandelson
Benjamin Wegg-Prosser, 31, current publisher of The Guardian newspaper's Society section, is due to take up the post in the autumn.
He was Mr Mandelson's researcher when New Labour first came to power in 1997.
He will replace Godric Smith, a civil servant who was a former official spokesman for the prime minister.
Mr Wegg-Prosser worked for Mr Mandelson before leaving in December 1998 and working briefly for media group Pearson Plc, before joining the Guardian in 2000.
The communications roles in Number 10 were reorganised following the resignation after nine years in 2003 of Mr Blair's former head of communications Alastair Campbell.
The role of prime minister's official spokesman, currently held by Tom Kelly, is not believed to be affected by the new appointment.
The prime minister's director of communications is the former Labour party head of press, David Hill, who replaced Alastair Campbell in that role.