Even nature has conspired against the project. Poor weather in southwest Japan has repeatedly delayed the delivery of heavy machinery to the island, further stalling the construction of vital port facilities.

“There is huge demand for more bases and greater infrastructure across southwest Japan as a result of the concentration of threats in the region of Okinawa and Kyushu,” said Ryo Hinata-Yamaguchi, an associate professor at Tokyo International University’s Institute for International Strategy.

A fleet of Chinese navy vessels has conducted what Japanese military analysts believe was an exercise to impose a naval blockade between the main island of Okinawa and the most westerly islands of the prefecture, isolating them as part of Beijing’s plans to take control of Taiwan.

Quoting multiple Japanese government sources, the Yomiuri newspaper reported on Wednesday that six Chinese ships – including a Jiangkai Class 1 frigate and three coastguard vessels – sailed around the southern tip of Taiwan before passing from the Pacific through the Miyako Strait and into the East China Sea on December 22.

The joint operation between the navy and armed coastguard vessels was the first in the 250km strait that separates Okinawa island and Miyako and an archipelago of smaller islands that ends with Yonaguni, a little over 100km to the east of Taiwan.

A Japanese government analyst said the ships’ movements were “an unusual move that suggests a maritime blockade”.

The exercises also coincided with the continued presence of Chinese coastguard ships in waters surrounding islands in the East China Sea that Beijing claims and refers to as the Diaoyu archipelago. The uninhabited territories are part of Okinawa prefecture and are administered by Japan, which knows them as the Senkakus.

Stephen Nagy, a professor of politics and international relations at Tokyo’s International Christian University, suggested the move could be “part of China’s broader strategy to take Taiwan without a fight”.

A central Japan city at the foot of Mount Fuji has lost more than a month’s worth of winter days per year in the past decade due to global warming, a recent study by a US-based climate research organisation showed.

The city of Fuji in Shizuoka Prefecture added 35 winter days above zero degrees Celsius annually on average between 2014 and 2023, the most among 901 Northern Hemisphere cities analysed, according to a December report by Climate Central.

The findings come as Mount Fuji received its first snowcap of the season on November 7 this year, the latest date since records began in 1894.

Japan's Mount Fuji snowless in October for first time in 130 years

More than half of 57 Japanese cities analysed saw climate change add at least two weeks’ worth of winter days above freezing each year, including Nagaoka in Niigata Prefecture and Kyoto, which saw an additional 23 days and 21 days, respectively.

As warmer winters could lead to water shortages due to reduced mountain snowpack, as well as increase the population of disease-carrying pests like mosquitoes and ticks, the organisation has stressed the importance of ending reliance on fossil fuels such as oil and coal as soon as possible.

“This warming trend, which is driven by human-caused climate change, not only disrupts the season itself but also erodes the benefits it provides year round,” the group noted.

The report, which compared observed December-February temperatures in the past 10 years with projected temperatures without human-induced climate change, found that around 44 per cent of the 901 cities analysed lost an average of a week or more of winter days annually due to global warming.