Meanwhile, the South China Morning Post says that the property is valued at between HK$3.1 billion and HK$5 billion (US$645 million), citing a tender document. Valuers also told the outlet that souring relations between the US and China, as well as the economic situation, may lower the price for the lot.

"Mainland Chinese used to be the buyers of luxury properties. Will they buy property from the US government now? That is a question in many people's mind," said Charles Chan Chiu-kwok, managing director of Savills Valuation and Professional Services Limited.

The US government has owned the land for 72 years after buying it for an unknown price. Back then, in 1948, Hong Kong was still a British colony.

A State Department representative told media that the sale was part of its global reinvestment program, that includes property reviews. The funds from the real estate deal can be reinvested in other areas.

"As part of that program, the State Department has decided to sell the Shouson Hill property, and at the same time, invest in enhancing other US government-owned assets in Hong Kong, including the US Consulate General's office building," a spokesman for the US consulate in Hong Kong said.

Earlier this week, US President Donald Trump announced that he wants to strip the Asian financial center of its trade and travel perks over Beijing's new security law. Hong Kong is already bracing for different scenarios as a result of the move, but Financial Secretary Paul Chan Mo-po says it will have little impact as its services sector dominates the local economy.