"As the result of a routine survey, an issue was found with one of the ceiling beams in the roof space of the state dining room," the spokesman said.
"Following further assessment, access to the room has been suspended as a precautionary measure while additional investigation work takes place."
The palace is Queen Elizabeth II`s London residence and where she hosts visits by foreign leaders, including Chinese President Xi Jinping last month.
Some of the palace`s 775 rooms have not been refurbished for 60 years and visitors have reported rain leaking near some of its precious paintings.
Extensive repairs are planned, costing an estimated £150 million (214 million euros, $226 million) and which could force the Queen to move out temporarily.
The building dates back to a large townhouse built on the site in 1703 but was enlarged in the 19th century.
Like Windsor Castle, the palace is owned by the state.
Buckingham Palace state dining room closed over safety fears
01 December 2015
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The state dining room of Britain`s Buckingham Palace, where visiting heads of state retire for coffee after banquets, has been closed off due to safety concerns, a palace spokesman said on Monday.
