England's 2018 World Cup delegation have made their final presentation in a bid to secure hosting the competition.
Prince William spoke on stage saying: I know that we can deliver extraordinary public occasions and celebrations.
Referring to his wedding to Kate Middleton he added: "I certainly hope so as I'm planning quite a big one myself next year."
"I give you an assurance that England is committed to playing its full and proper role in developing football internationally as a member of your global footballing family."
In his speech, David Cameron promised England would lay on "the most spectacular World Cup in history".
He said fans from all over the world would feel at home in England's diverse cities.
Mr Cameron pointed out that many of the world's biggest stars play in the English Premier League, which is watched all over the world.
He promised Fifa executives that an English tournament would not just be a commercial success but a "global event".
And he added: "We have the expertise, we have the stadiums, we have the fans. We have what it takes."
England are in with a real chance of a shock victory in today's Fifa vote for the 2018 World Cup hosting rights after a pronouncement by Vladimir Putin looked to have caused serious damage to rivals Russia.
England now look to be neck-and-neck with Spain/Portugal though bid leaders accept there is still much uncertainty surrounding the secret ballot of the 22 Fifa executive committee members.
Holland/Belgium are also in the running, though they are very much the outsiders.
