Britain's Prince Andrew rappelled 239 metres down the side of Europe's tallest building today to raise money for charity.

The 52-year-old's stunt began on London skyscraper The Shard's 87th floor and finished on the 20th in 30 minutes.

Following the descent Monday morning, the prince said: "I will never do it again."

Andrew was part of a group of about 40 participants raising funds for the Outward Bound Trust and the Royal Marines Charitable Trust Fund.

The prince, chairman of the trustees of the Outward Bound Trust, raised the equivalent of $460,000 US.

Following the stunt, Andrew told reporters the "difficult bit was actually stepping out over the edge," but said his training with the Royal Marines had given him the confidence.