Sir Terry Wogan will raise Tower Bridge and receive the Freedom of the City of London to celebrate five decades in broadcasting, and to mark his final week presenting Wake Up to Wogan on BBC Radio 2.
Sir Terry has been invited by the City of London Corporation, which owns Tower Bridge, to raise the two 1,100-tonne bascules at 11.15am on Monday 14 December to allow a vessel to pass.
While he is operating the machinery, Sir Terry will make a series of announcements over the Bridge's public address system to warn drivers, pedestrians and technical staff about its imminent closure and reopening.
"For years I've been hoping to drive a herd of sheep over London Bridge," says Sir Terry. "Or failing that, swinging from the Tower on a silken rope."
Nick Anstee, Lord Mayor of the City of London, said: "I am delighted to nominate Sir Terry for the Freedom of the City of London to help celebrate his outstanding work, whether it's entertaining millions of people on Wake Up to Wogan or raising millions of pounds for Children in Need.
"I am sure that pedestrians and car drivers on Tower Bridge will be pleasantly surprised to hear his dulcet tones over the Tannoy when he stops the traffic… but I don't hold out much hope for his sheep herding plans."
After the bridge lift Sir Terry and his guests will be driven to Mansion House where he will receive the Freedom of the City of London.
He will be joined by Lord Mayor Nick Anstee and Stuart Fraser, City of London policy chairman, who both nominated him for his Freedom, as well as members of his family and BBC colleagues.
The ceremony, which will be presided over by Christopher Bilsland, Chamberlain of London, will begin with an oath of allegiance (to HM The Queen and the Lord Mayor, read aloud by Sir Terry) and end by him being greeted as a 'Citizen of London' and the presentation of a framed copy of his Freedom certificate.
After the ceremony the Lord Mayor and the Chamberlain will host a private lunch at Mansion House for Sir Terry and his guests.
Many of the traditional privileges associated with the Freedom, including driving sheep over London Bridge and being drunk and disorderly in the City without fear of arrest, no longer exist.