Mainland's telecommunications tower operator China Tower is looking to open the retail book for its HK$68.1 billion ($8.7 billion) IPO on Wednesday in Hong Kong.

With trading scheduled for Aug 8, 2018, the blockbuster flotation could be largest in Hong Kong since Agricultural Bank of China's HK$93.5 billion deal in 2010. It could become the biggest float globally in the nearly four years since Alibaba's $25 billion New York listing.

The State-owned conglomerate plans to sell 43.1 billion shares at HK$1.26 to HK$1.58 apiece, with a minimum investment of HK$3,191.84 for a board lot of 2,000 shares.

Valued at up to $35 billion, China Tower has lined up more than HK$10.9 billion from 10 cornerstone investors, including Hillhouse Capital Group and Taobao China Holding Ltd, with a six-month lock-up period.

But, as escalating Sino-US trade tensions cast a shadow over the city's stock market, analysts said the company could face a tough reality check amid muted investor demand and lackluster market performance.

Since it filed the IPO application in May this year, China Tower has already slowed down its fundraising pace, amid lukewarm market performance and bearish investor sentiment.

"As Xiaomi was given the cold shoulder and was forced to trim its listing by almost one-fourth, China Tower is ready to put its business to the verdict of investors and may not be lucky enough to fare better," said Chan Pingkeung, chief investment officer of Hong Kong-based World Group Asset Management.

As the Sino-US trade dispute rages, the flagship Hang Seng Index has dropped roughly 4.2 percent so far this year. A flotation on this scale would pull an enormous amount of money from the local market, which has already run into a rough patch amid the global sell-off, Chan said.

The benchmark Hang Seng Index was up 1.44 percent, or 406.45 points, to finish at 28662.57 points on Tuesday.

Beijing-based China Tower was founded in 2014 from the combined tower assets of the country's three State-backed Hong Kong-listed telecoms providers - China Mobile Communications Corp, China Telecommunications Corp and China United Network Communications Group Co Ltd.

Before the mega-sized IPO, China Mobile owned 38 percent of China Tower, China Unicom held 28.1 percent and China Telecom had 27.9 percent.