The 37-storey Walkie-Talkie skyscraper, officially known as 20 Fenchurch Street, is now believed to be fully let, according to the London Evening Standard. It was one of the first major office buildings in the City to be built after the financial crisis and apart from office space has a popular Sky Garden open to the public at the top.

The Chartered Institute for Securities and Investment will take take the last remaining space on the third floor in the tower, says the Standard.

The tower was branded the “Walkie-Scorchie” by some in 2013 because the sun's rays from the concave glass surfaces cladding the building reportedly melted bodywork on nearby parked cars and enabled one reporter to fry an egg on nearby surfaces. The problem was solved by fitting a permanent sunshade to the top of the building.

In a message to members the CISI said: "We will soon be relocating to the third floor of the Walkie Talkie building in Fenchurch St, because we have outgrown our current premises. Plans for the relocation are still being finalised, but we hope to be in the new premises by the summer.

"The rent for this new office space is average, not premium, and is less than what we would pay if we were to remain at our current location. The lease on our current premises is due to end in August 2017."

"This information was reported in the London media yesterday, without our prior knowledge, and we would like to apologise to our members that this information was not able to be made to you directly by us."

Further information about the relocation plans will be released to members soon, said the CISI.