An updated design for Junya Ishigami’s Cloud Arch sculpture has been approved by the City of Sydney. The new sculpture is almost twice the size of the initial design proposal, and almost triple the price.

According to the Sydney Morning Herald, the sculpture’s approval was the cause of much contention in a council meeting earlier in the week. The $11.3-million sculpture – initially estimated at $3.5million – was approved by six votes to four after more than an hour of “heated debate”.

Japanese architect Junya Ishigami initially unveiled his architectural sculpture in 2014, as one of the three public artworks commissioned as part of the City of Sydney’s City Centre Public Art Plan. All three artworks were unanimously chosen by a jury panel, who sifted through more than 700 expressions of interest from around the world.

Ishigami has described the Cloud Arch sculpture as an “ethereal ribbon” that “behaves like a flicker”.

“Cloud Arch will function like a gateway, allowing trams and people to pass under it and framing the important monuments and buildings of Sydney,” says Ishigami in a design statement.

“The cloud evokes a spirit of openness and freedom. The soaring arch, by reaching for the sky, encourages people to dream and to be bold in striving to realise their ambitions.”

The sculpture has been pegged by architect Penelope Seidler as “the most exciting design to emerge on the Sydney scene since the Opera House”. Reaching 58 metres into the air, Cloud Arch will hover over the intersection of George and Park Streets near the Queen Victoria Building, framing Town Hall.

Despite being made from 140 tonnes of steel, Ishigami says his aim was to create a structure that looked “impossibly thin and light”.

The construction of Cloud Arch has experienced delays due to the light rail transport infrastructure currently being built along George Street. However, the structure is expected to be complete by March 2019.