London's mayor Sadiq Khan has blocked plans for a controversial tower known as the Tulip, saying the structure would be of "limited" public benefit and "detrimental" to the capital's skyline, CNN reports.

In a letter explaining the decision, Khan said the proposal "would not constitute the high standard of design required," and that it would "cause harm to the historic environment, the wider skyline and image of London."

The move comes less than four months after city authorities gave a green light to the 1,000-foot-high attraction, which would have become the second-tallest skyscraper in western Europe upon opening in 2025.

Designed by the prominent architect Norman Foster's firm, Foster + Partners, the proposed tower featured viewing platforms, restaurants and educational facilities for children. The design also envisaged a collection of rotating glass pods that would transport visitors around the building's exterior.

But the proposal attracted criticism from social media users and heritage groups after it was unveiled in November 2018. London's City Airport, located just six miles away, even sought assurance from city planners that the moving pods wouldn't interfere with air traffic control systems.

Nonetheless, plans were approved by the City of London Corporation, which governs the City of London. Its Planning and Transportation Committee voted 18-7 in favor of the project in April.