Satellite images appear to show that Cuba is building a new radar site likely to be capable of spying on the US’s nearby Guantánamo Bay naval base, in the latest upgrade to the country’s surveillance capabilities long thought to be linked to China. The base, under construction since 2021 but previously not publicly reported, is east of the city of Santiago de Cuba near the El Salao neighborhood, the Center for Strategic and International Studies (CSIS) said in a report published on Monday and later referenced by the Wall Street Journal. Cuban vice foreign minister Carlos Fernandez de Cossio denied that Cuba was harboring Chinese military interests on the island. “[The] Wall Street Journal persists in launching an intimidation campaign related to #Cuba. Without citing a verifiable source or showing evidence, it seeks to scare the public with tales about Chinese military bases that do not exist and no one has seen, including the US embassy in Cuba,” de Cossio said on social media. Cuba’s proximity to the US and its southern military bases makes it a good location for China, Washington’s top strategic rival, to seek to collect signals intelligence. The CSIS called the new site a “powerful tool” that once operational will be able to monitor air and maritime activity of the US military. The facility, known as a circularly disposed antenna array with a diameter of approximately 130-200 meters, could be able to track signals as far as 3,000-8,000 nautical miles (3,452-9,206 miles) away, the CSIS said. “Access to such an outpost would provide China with a highly strategic vantage point near Naval Station Guantanamo Bay,” it said, referring to the key US military base 45 miles (73km) east of Santiago, Cuba’s second largest city. Such arrays were used heavily during the cold war, but Russia and the US have since decommissioned most of their sites in favor of more advanced technology, the CSIS said. However, the thinktank said China has been actively building new such arrays, including on reef outposts in the South China Sea. Last year, Biden administration officials said Beijing has been spying from Cuba for years and made a push to upgrade its intelligence collection capabilities there beginning in 2019, allegations that both Beijing and Havana have denied. State Department spokesperson Vedant Patel declined to comment on the report, but told a briefing on Tuesday that the US was “closely monitoring” China’s presence in Cuba. “We know that the PRC [People’s Republic of China] is going to keep trying to enhance its presence in Cuba and the United States is going to keep working to disrupt it,” Patel said without giving details. The White House national security council and the US defense department did not immediately respond to requests for comment. China’s embassy in Washington said the US had repeatedly “hyped up” the idea of China’s spying and surveillance from Cuba. “Such claims are nothing but slander,” embassy spokesperson Liu Pengyu said. The CSIS also said satellite images from March 2024 show Cuba’s largest active signals intelligence site at Bejucal, located in the hills near Havana and linked to suspected Chinese intelligence activity for years, has undergone “major updates” in the past decade, calling it a “clear indication of an evolving mission set”. “Collecting data on activities like military exercises, missile tests, rocket launches and submarine maneuvers would allow China to develop a more sophisticated picture of US military practices,” the CSIS said. It said certain radar systems installed in Cuba in recent years are in range to monitor rocket launches from Cape Canaveral and Nasa’s Kennedy Space Center, a likely interest for China as it seeks to catch up to US space launch technology.