Roads immediately surrounding Buckingham Palace have been closed and are accessible only on foot, as the royal family prepares for the Queen to Lie in State.
The Metropolitan Police issued a map showing the areas where vehicles are banned, including around Green Park and St James' Park.
Bicycles can be pushed but not ridden within the zone.
"Although we recognise these road closures may cause some inconvenience, they are necessary to ensure the safety of those members of public visiting London and to allow the planned ceremonial events to take place," a Met statement said.
The Queen's coffin arrived at Buckingham Palace on Tuesday evening to cheering crowds paying tribute, after thousands lined the route along her final journey back to London.
The King and his sons will walk behind the Queen’s coffin this afternoon as she leaves Buckingham Palace for the final time ahead of her lying in state at Westminster Hall.
From 11am on Wednesday, procession viewing areas will open to the public along the route, with large crowds expected to attend.
An area at Hyde Park where the public can watch the procession via big screen will also open.
The Queen will Lie in State for four days, during which time the queue for those wishing to pay their respects could stretch all the way to Southwark Park in south-east London, according to the government plan.
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