He greeted volunteers hard at work on board the London Poppy Day red bus at Clarence House as part of a campaign to raise £1m in a single day from donations across the capital.
Television presenter and Poppy Day ambassador Ben Shephard said the Prince spent some time joking and laughing when he boarded the Routemaster.
“We thought we could try and drive off with him on the bus and launch a ransom to raise more money,” Shephard said. “But he thought that we wouldn’t get very far.”
The Prince also joked about having a sing-along on the bus and riding a Harley Davidson before meeting motorcyclists from the Royal British Legion Riders Branch.
He then met volunteers inside Clarence House’s Poppy Day counting room, where the money raised for the Poppy Appeal is rapidly totted up using machines.
Hundreds of volunteers have been given the important task of tallying the collected donations at five counting stations across the capital, including, for the first time, the one at Clarence House.
The Royal Mint is also playing its part in fundraising with the launch of its first commemorative £5 coin for Remembrance Day.
A donation will be made to the Royal British Legion for every coin sold.
The coin, designed by Royal Mint engraver Emma Noble, features the words “the eleventh hour of the eleventh day of the eleventh month”. It is available from the website www.royalmint.com
Meanwhile it has been revealed that a war memorial at Gillamoor, near Kirkbymoorside, will be rededicated in a ceremony next Friday at 3pm.
Residents of the North Yorkshire village were devastated when a motorist demolished the much-loved memorial – but a replica has now been carved and placed on the village green.