Tobu Railway Co. and others held a ceremony Monday to mark the beginning of construction of the 610-meter Tokyo Sky Tree in Sumida Ward, scheduled for completion in spring 2012.
A prayer was offered for the safety of construction workers at the site of the new radio and TV transmission tower.
Tokyo Sky Tree, which will be one of the world's tallest radio and TV transmission towers, is to commence operation in spring 2012.
NHK and the five major commercial broadcasters are currently using Tokyo Tower to transmit both analog and digital TV signals.