The 52-storey tower has been designed by architects Rogers Stirk Harbour + Partners and Arups, for British Land Company PLC and Oxford Properties.
The 610,000 sq ft development will feature a tapered glass façade on one side which will reveal the steel bracings combined with a complex ladder frame aimed to enhance its vertical appearance.
The base will feature a 30 metre high atrium. It is set to become one of the tallest buildings in the City of London.
Chief operating officer for Severfield-Rowen, Peter Emerson, said: “Leadenhall Street is a significant contract award for Severfield-Rowen and will be produced across all of our four manufacturing facilities in the UK.
“The steelwork programme will commence later this year and complete during 2012.”