WASHINGTON, June 11 (AFP) - China has been operating an intelligence unit in Cuba for years and upgraded it in 2019 in an effort to enhance its presence on the Caribbean island, a White House official said on Saturday (Jun 10).

"This is well-documented in the intelligence record," the official, who spoke on condition of anonymity, said in confirming China's intelligence presence.

US media in recent days had reported that Beijing was planning to set up a spy base on the island, which is located just off American shores.

When President Joe Biden took office in January 2021, "we were briefed on a number of sensitive PRC efforts around the world to expand its overseas logistics, basing, and collection infrastructure globally," the administration official said, using an acronym for the People's Republic of China.

"This effort included the presence of PRC intelligence collection facilities in Cuba," the official said. "In fact, the PRC conducted an upgrade of its intelligence collection facilities in Cuba in 2019."

The developments come as Chinese leader Xi Jinping has pushed a rapid expansion of the country's security presence around the world.

US Secretary of State Antony Blinken is scheduled to travel to China next weekend, rescheduling a visit that was cancelled in February after a tension-filled incident involving a suspected surveillance balloon passing over the United States.

A base in Cuba, which lies 150km off Florida's southern tip, would present the most direct challenge yet to the continental United States.

China warned the United States on Friday against "interfering in Cuba's internal affairs", in response to the media reports on a planned base.

When asked about the base at a regular press briefing, Chinese foreign ministry spokesperson Wang Wenbin said he was "unaware of the situation" before criticising US policy on Cuba.

"As we all know, spreading rumors and slander is a common tactic of the United States, and wantonly interfering in the internal affairs of other countries is its patent," said Wang.

The US official said the administration believes that diplomatic efforts "have slowed the PRC down" in developing its activities in Cuba.

"We think the PRC isn't quite where they had hoped to be," the official said.

Earlier this year, China sent what the US called a high-altitude surveillance balloon across the United States. It floated from west to east above sensitive military installations before it was shot down by a US fighter jet.