Veteran broadcaster Sir David Attenborough has undergone surgery to insert a pacemaker.
A spokesman for the 87-year-old naturalist, who was forced to cancel a sell-out speaking tour of Australia because of the "urgent'' procedure, said doctors believed that the TV star was doing well.
"Sir David has now had the operation and his doctors are satisfied with his progress," he said.
Earlier, he said the documentary-maker, who has been named Britain's greatest living national treasure, was still his "lively self".
"It's a minor procedure but it meant that he cannot go on a 27-hour flight to Australia," he said.