Buzz Aldrin, the former US astronaut and the second person to set foot on the moon, was evacuated from the South Pole because of a medical condition, a tourism company said.

Aldrin, 86, was visiting the South Pole as part of a tourist group when his condition deteriorated, the company White Desert said in a statement.

He was evacuated on the first available flight out of the South Pole to McMurdo Station, a nearby U.S. research base, under the care of a doctor, and his condition was stable, the company said. McMurdo is on Ross Island, just off the coast of Antarctica.

The company's statement, which was posted on the website of a tourism trade group, did not specify the ailment.

A former fighter pilot, Aldrin stepped on the moon about 20 minutes after Neil Armstrong took the historic first step on July 20, 1969.

Their moonwalk as part of the Apollo 11 lunar landing was watched by a then-record television audience of 600 million people.

The U.S. National Science Foundation, which manages the U.S. Antarctic Program, said Aldrin would eventually be evacuated to New Zealand.