The Met Police will be working with the City of London Police, who cover the capital's financial district, and the British Transport Police, as well as the country's intelligence agencies and other partners to keep the city safe, Jones said.
At the same time, she sought to downplay concerns that things may get out of hand despite the large scale of Wednesday's operation.
"We have a lot of experience in the Metropolitan Police -- in fact, really, this is our bread and butter," she said.
The threat level assessment from Britain's intelligence experts has not changed, she said.
Last year, policing efforts were dominated by the Diamond Jubilee, celebrating the queen's 60 years on the throne, and the London Olympics, which passed off peacefully. The wedding of Prince William and Catherine in April 2011 also involved a major policing operation.
Public confidence in police was shaken, however, by several nights of riots and looting that rocked London and other English cities in the summer of 2011.
The Olympics security operation included warships moored in the Thames, Typhoon jet fighters and Puma helicopters on standby, and, perhaps most controversially, surface-to-air missiles on apartment buildings near the Olympic Stadium.
Jones would not give any detail of extra measures to be taken Wednesday, saying only that police "will deploy the resources we need to ensure that this is a safe and secure event."
"Protective measures for the royal family, visiting heads of state and others -- that is normal practice, and it is absolutely tried and tested tactically," she said.
"It's the way we have managed to secure so many very successful events in London against a backdrop where we often have counterprotests going on."