Eleven people were evacuated from the building, which also houses The Law Society Gazette, as 150 firefighters fought the blaze at Chancery Lane at around 10:40 pm.

A junior lawyers division dinner had been taking place, no one was injured.

113 Chancery Lane was constructed in 1832, seven years after the society itself was created, and is a grade two listed building.

Law Society chief executive Paul Tennant said: “First of all I wanted to express my gratitude to the fire service and my relief that nobody has been hurt. I also want to express my sympathy to the residents in the Chancery Lane area whom I understand may have had to evacuate their homes.

“It is too early to comment on the cause of the fire or the extent of the damage but clearly we are extremely upset that this has happened to this wonderful and historic building.

“When the fire alarm sounded on Saturday night an event had been taking place. An evacuation ensued and I’d like to praise our on-site staff and others for their calm response. We will release more information as it emerges in due course.”