Mourners have been asked to stop leaving marmalade sandwiches and Paddington Bear toys at tribute sites to the Queen.
The Royal Parks said non-floral objects should not be left in London's royal parkland.
An increasing number of Paddington-themed tributes have been left in reference to a TV sketch the late monarch filmed with the iconic bear for her Platinum Jubilee celebrations.
During the sketch, in which the pair share tea at Buckingham Palace, Paddington pulls his favourite food - a marmalade sandwich - from under his hat, before the Queen surprises him by revealing she keeps her own marmalade sandwiches in her Launer handbag.
“Unfortunately, no gifts and artefacts will be accepted and the public will be asked not to bring these to the parks," the Royal Parks said.
“Non-floral objects/artefacts such as teddy bears or balloons should not be brought.”
Thousands of well-wishers have laid flowers close to Buckingham Palace, Windsor Castle and Balmoral since the monarch’s death was announced on Thursday.
People are invited to leave flowers, without any wrapping, at a dedicated site in Green Park close to the late Queen’s London residence, the Royal Parks said on its website.
The floral shrines at royal residences over the last few days have also included Corgi soft toys and balloons.
See the timetable of planned official events in the historic days ahead
They added that it will not be possible to light candles in the parks and that lit candles will be extinguished.
Tributes will be left on site until all ceremonial activity has taken place and it is expected that flowers will be removed from park areas from seven to 14 days after the date of the funeral.
Flowers that have deteriorated will be removed throughout and taken to the Hyde Park nursery for processing to prepare them for composting.
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