The Duke of Sussex closed a £1 billion deal on a financial trading floor as he helped raise thousands of pounds for charity including his Invictus Games.

Armed with three phones as traders barked orders at him, Harry kept his cool and managed to seal the transaction, which is estimated to have raised £50,000.

The duke was one of a host of celebrities including comic Jimmy Carr, Game Of Thrones star Kit Harrington, London Mayor Sadiq Khan, former England football manager Sam Allardyce and England World Cup-winning cricket captain Eoin Morgan taking part in the BGC charity day.

The annual event is staged by BGC Partners brokerage at its offices in London’s Docklands to commemorate 658 Cantor Fitzgerald staff and 61 EuroBrokers employees who died in the attack on the World Trade Centre in New York on September 11 2001.

BGC Charity Day 2019 – London
The Duke of Sussex juggles three phones, assisted by former Invictus Games competitor Paul Vice (left) (Kirsty Wigglesworth/PA)

At the Gilts desk, which trades in Government debt, Harry completed the huge trade under the watchful eye of Ryder Brown, co-head of the department.

Mr Brown said the duke had done the difficult job of closing a £1 billion trade in 10-year gilts.

BGC Charity Day 2019 – London
The Duke of Sussex chats to former England football boss Sam Allardyce (Kirsty Wigglesworth/PA)

He added: “I thought he was excellent. It was very nerve-wracking but he handled the pressure well and closed the trade.

“That was the hard bit, to close the trade. He picked the telephone up and managed to do it – it’s like old-style trading.”

BGC Partners is a company of City brokers, earning commission for the deals they facilitate between financial clients, and during the charity day a percentage of the funds earned will be donated to good causes.

BGC Charity Day 2019 – London
Comedian Jimmy Carr also took part in the 15th BGC annual charity day (Ian West/PA)

When Harry first arrived on the trading floor he stopped at the “Euro Swap” desk where traders shouted potential deals at each other. When handed a phone he had to stick a finger in his ear to block out the noise.

He followed the orders of staff around him as he finished a £75 million deal and at one point said to the client on the end of the line, “come on, just one more”.

When the deal was done another, this time worth £100 million, was offered and he told the unknown trader on the phone “we’re working your order”, then added “can you improve your offer” when prompted by a BGC trader to say the words.

Gabby Logan
Gabby Logan was among those lending their support (Ian West/PA)

Finally a round of applause went up when the transaction was completed.

Earlier Harry had met Invictus Games competitors when he arrived and he was joined on the trading floor by former Royal Marine Paul Vice, who has competed in the duke’s competition for injured and wounded service personnel and veterans.

Mr Vice, who at one point held a phone under the duke’s chin while Harry had one in each ear, said: “That was stressful, but it was good fun.”