Sir Charles will act as a figurehead, welcoming and hosting dignitaries and maintaining a "visible and accessible" presence for residents throughout the Games period.

Once chief executive of ITV, Sir Charles, 55, cut his teeth in the specialised business of hosting sports mega-events when he acted as chair of the Organising Committee for the 2002 Commonwealth Games in Manchester.

He has been a key behind-the-scenes figure at London 2012, first as vice-chair of the victorious London bid and more recently as a director of the Games Organising Committee.

He says he is "thrilled" by his appointment and looking forward to delivering "an outstanding and memorable experience for residents and visitors during the Games this summer".

Lord Coe, the London 2012 chairman, said Sir Charles had "a thorough understanding of the Games environment and its complex delivery".

He was confident he would do a "fantastic" job.

Baroness Tanni Grey-Thompson, multi-Paralympic gold medallist and deputy chair of the London 2012 Athletes' Committee, said: "When an athlete arrives at the Village to prepare for the biggest moment in their sporting career it's important that the welcome they receive sets the tone for the days and sometimes weeks ahead".

Allen, she said, "understands this and will ensure it happens seamlessly".

Among other current roles, Sir Charles is a director of Virgin Media.

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