“The Tulip” has been put forward by Gherkin owner J. Safra Group and architects Foster + Partners.

Construction could start as early as 2020 on the 305.3-metre-high visitor attraction which is due for completion by 2025.

The top of The Tulip will feature an education centre offering 20,000 free places per year for London’s state school children.

It will also provide an unparalleled vantage point to view London from a height of around 300 metres.

The viewing galleries will offer visitors an engaging experience with sky bridges, internal glass slides and gondola pod rides on the building’s façade.

Complementing the experience will be a sky bar and restaurants with 360-degree views of the city.

The Tulip will use high performance glass and optimised building systems to reduce its energy consumption.

Heating and cooling will be provided by zero combustion technology while integrated photovoltaic cells generate energy on site.

Norman Foster, Founder and Executive Chairman, Foster + Partners said: “Continuing the pioneering design of 30 St Mary Axe, the Tulip is in the spirit of London as a progressive, forward-thinking city.

“It offers significant benefits to Londoners and visitors as a cultural and social landmark with unmatched educational resources for future generations.”

Jacob J. Safra said: “We are delighted to benefit from the exceptional talent of Foster + Partners in bringing to London this world-class visitor attraction.

“The Tulip’s elegance and soft strength complements the iconic Gherkin.

“We are confident in London’s role as a global city and are proud to offer its schoolchildren a state-of-the-art classroom in the sky to appreciate London’s history and dynamism.”