About 100 firefighters are battling a blaze at Somerset House in central London.
Fifteen fire engines and about 100 firefighters were at the scene, London Fire Brigade said.
"Crews are tackling flames located in part of the building's roof," the fire brigade said.
https://twitter.com/LondonFire/status/1824782584317927934https://twitter.com/SomersetHouse/status/1824791451533734063
"Two of the Brigade's 32m ladders have been sent to the scene to support firefighting operations.
"The entire site at Somerset House is now closed to the public whilst we tackle the fire.
"Traffic in the surrounding area will be impacted as crews respond."
The first call about the fire was received at 11.59am on Saturday (9pm AEST).
Somerset House said all staff and members of the public who are at the venue are safe.
Somerset House is an iconic building on the Strand, near to the Australian High Commission, and at its southern end overlooks the River Thames.
Built in the mid-1500s, the future Queen Elizabeth I lived at Somerset House until 1558.
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