A man who parked on Eastcheap near the building, which is designed by architect Rafael Viñoly and is being developed by Land Securities and Carary Wharf, claimed the light bouncing off the tower’s glazing melted parts of his Jaguar XJ.

The owner of the Jaguar, Martin Lindsay, parked his car in one of the bays last Thursday only to return to find plastic panels and a wing mirror had warped.

The City of London has now halted use of three parking bays on the street. A spokesperson for the local authority said the cause was being investigated.

Lindsay told City AM: “They’re going to have to think of something. I’m gutted. How can they let this continue?”

The paper also spoke to Eddie Cannon, a heating and air conditioning engineer, who said his Vauxhall van had suffered similar damage the day before: “The van looks a total mess – every bit of plastic on the left hand side and everything on the dashboard has melted.”

In a joint statement the two developers said: “We are aware of concerns regarding the light reflecting from 20 Fenchurch Street and are looking into the matter.”

The top-heavy design of the new tower is partly intended to maximise floor space towards the top of the building, where rent is typically higher.

It will be clad with double- and triple-glazed panelised aluminium cladding. The botanical gardens at the top of the building will be London's highest public park — marginally higher than Rickman Hill Park in Coulsdon at 155 m above sea level at its highest point. The gardens will span the top three storeys, will be accessible by two express lifts, and include a viewing area, terrace, café, bar and restaurant. Fourteen double-deck lifts (seven low-rise up to the 20th floor, seven high-rise above the 20th floor) will serve the main office floors of the building.

The south side of the structure will be ventilated externally to improve efficiency and decrease solar gain, whilst the east and west faces incorporate extensive solar shading.The tower was originally proposed at nearly 200 metres tall but its design was scaled down after concerns about its visual impact on the nearby St Paul's Cathedral and Tower of London.