George Alagiah is to become the sole presenter of the BBC's Six O'Clock News following the departure of Natasha Kaplinsky.
She is leaving the BBC to join Five News in a deal believed to be worth £1m a year.
The Six O'Clock News has had two presenters since January 2003. BBC insiders believe the return to a single presenter is part of plans by the head of BBC Television News, Peter Horrocks, to cut costs.
Alagiah, who joined the Six O'Clock News in 2003, said he felt "honoured" to be asked to present on his own.
Peter Horrocks said: "The Six O'Clock News will be built around George's warmth and great experience. He has enormous versatility - being as comfortable with reporting from scenes of flood devastation as from Downing Street.
"The bulletin has a special remit to report fully stories from around the UK and we will be devising plans with George to fulfil this objective, at a time when our competitors are reducing their commitment to the regions of the UK."