The Garden Bridge Trust has announced that it is winding up the controversial project due to a lack of support from the mayor of London.
In April, Sadiq Khan said he would not provide the financial guarantee needed for planning permission.
First proposed in 2013 after a suggestion from actor Joanna Lumley to then mayor Boris Johnson, the free bridge would have enabled millions of Londoners and tourists to enjoy stunning views across the River Thames.
The decision to scrap the plan means that about £37m of public funds already spent on preparatory work and in trying to overcome legal and planning hurdles will be lost.
According to the BBC, since the mayor's decision to withdraw the financial guarantee, the trust has been looking at other funding options, including speaking to the UK government. It said that all potential benefactors and trustees decided the project could not happen without the support of the mayor.
The project’s backers included Lord Rogers and Olympic designer Thomas Heatherwick, who was commissioned to draw up plans for the bridge.
In a letter to Mr Khan, the trust's chairman Lord Davies said: "We are incredibly sad that we have not been able to make the dream of the Garden Bridge a reality and that the mayor does not feel able to continue with the support he initially gave us."
He said the trust had raised £70m of private money towards the project and had satisfied most of the planning permission conditions.
"The Garden Bridge would have been a unique place; a beautiful new green space in the heart of London, free to use and open to all, showcasing the best of British talent and innovation," Lord Davies said.
"It is all the more disappointing because the trust was set up at the request of TfL (Transport for London), the organisation headed up by the mayor, to deliver the project. It is a sad day for London because it is sending out a message to the world that we can no longer deliver such exciting projects."
Commenting on the decision to end the project, Mr Khan said it was his "duty to ensure taxpayers' money was spent responsibly".
"I have been clear since before I became mayor that no more London taxpayers' money should be spent on this project and when I took office I gave the Garden Bridge Trust time to try and address the multiple serious issues with it.
"Londoners will, like me, be very angry that London taxpayers have now lost tens of millions of pounds - committed by the previous mayor on a project that has amounted to nothing."