Police have urged those who attend events to mark the 70th anniversary of VJ Day on Saturday to be "vigilant and alert".
Reports have claimed the commemorations could be targeted by terrorists but earlier this week Scotland Yard encouraged people to continue with their plans as normal.
The Queen will lead the country in recalling the sacrifices of British Second World War forces who fought and died defeating Japan.
She will be joined by other members of the royal family and Prime Minister David Cameron in a series of events marking VJ Day - Victory over Japan - which are expected to be watched by thousands of people.
Metropolitan Police Commander Dave Musker, who is in charge of policing plans, said: "We have reviewed our security plans for this event and I want to reassure people that we will continue to work hard to ensure that this is a safe and secure event.
"I would also like to reiterate our long-standing advice to residents and visitors to remain vigilant and alert."
A large security operation will be in place in the capital, with road closures in central London between 6am and 5pm.