The Duke of York, fourth in line to the throne, will make the attempt on September 3, in support of The Outward Bound Trust educational charity and the Royal Marines Charitable Trust Fund, which benefits serving and retired troops.

It is hoped that more than £1 million ($1.5 million, 1.3 million euros) will be raised.

"I am delighted to be leading the descent of the Shard," said Andrew, Outward Bound's chairman of trustees.

"I am also very proud... of the work the trust undertakes with young people to give them challenge through adventure."

Aged 52, Queen Elizabeth II's second son is a Royal Navy commander who served in the 1982 Falklands War.

He officially launched the building on July 5 along with Qatari Prime Minister Hamad bin Jassem al-Thani.

The 310-metre (1,017-foot) tall tower, close to London Bridge on the south bank of the River Thames, was inaugurated with a sound and light show.

The £450 million ($700 million, 570 million euro) project, designed like a shard of glass, was 95 percent funded by Qatar.

Andrew will abseil 250 metres (820 feet) from the 87th to the 20th floor.

Some 40 people will join in the abseil, with half going down to the 20th floor and the remainder descending to the 78th.

Ffion Hague, the wife of Foreign Secretary William Hague, is among those involved.

Iain Peter, a mountain guide in charge of the abseil, said the fact that the outside of the building is glass represented a tougher challenge than going down a mountain.

"It is going to be terrifying," The Times newspaper quoted him as saying.

"The height is the craziest thing."