(ABC News) -- Princes William and Harry dressed in formal suits and ties to take on the roles of professional traders for a charity event today in London, but it didn't take long for the brothers to devolve into a comedy routine.
"Stop flirting, get on with it," Harry, 28, said to his older brother when he saw William, 31, on the phone with a female trader.
"Bloody hell, was that a billion?!" William said after the two princes sealed a deal that broke a record for a forward foreign exchange trade, according to the UK's The Telegraph.
The two royal heirs traded in their crowns for telephones and briefcases to raise money in memory of the 658 employees of BGC Partners, a global brokerage company, who died in the Sept. 11 attacks on the World Trade Center 12 years ago.
At one point during the one hour that the princes spent on the trading floor, Prince Harry joked with his older brother, a new dad to son Prince George, for being one of those new parents who only talks about their child.
"He's on the phone, it's all baby chat," Harry said, while later telling another broker named George that he had a "good, strong name."
While kidding about his brother's focus, Harry wasn't entirely incorrect. William was, in fact, talking on the phone about his newborn, revealing that things are improving for his son, whom just weeks ago he called "a little bit of a rascal."
"He's very well, thanks. He's sleeping quite well," William said.
Not to be outdone by his prankster brother, William got in on the laughs too, telling one person on the other end of the line who couldn't believe he was talking to a future King of England, "It's all a wind-up, I'm Gary."
The money raised at the event by the princes and other celebrities, including Rod Stewart, Thandie Newton and David Hasselhoff, will be split among charities, according to the Telegraph. William and Harry were on hand to raise money for SkillForce, of which William is a patron, and WellChild, which Harry supports.
Though both princes got the seal of approval from the real-life brokers who coached them through their role playing - with one saying Harry in particular "took to it very well" - don't expect to see the royals giving up their day jobs.
"I'm much better at helicopters," Harry said on the floor, referring to his day job as Captain Wales, an Apache attack helicopter pilot in the British Army.
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