The British-designed 'Gate of the Orient' in Suzhou in the Jiangsu province cost £445 million ($712m) to construct and comprises 69 storeys.
It had been hyped as the 'Arc de Triomphe of the East', but received criticism from the Shanghai Daily newspaper, who printed on the front page: "Is it an arch or just plain pants?"
People have taken to the internet to vent about the building. One blog poster said that walking through it would be "humiliating" and "like being forced to crawl between someone else's legs".
RMJM, the architecture company responsible for the 300-metre skyscraper, stated: "The Gate to the East introduces a dramatic iconic 'gateway' to the city of Suzhou and represents the significance of... China in the world today."
The building, once complete, will feature a hotel in addition to office, retail and residential living space.
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