Nelson Mandela left waiting in the cold as ambulance breaks down

An ambulance taking former president Nelson Mandela to hospital for emergency treatment broke down on a motorway, forcing him and his doctors to wait for up to 40 minutes in the cold, South Africa's presidency confirmed on Saturday.

Mandela, 94, was taken from his home in Johannesburg to hospital in Pretoria in the early hours of June 8 after his doctors decided he needed intensive care for a recurring infection.

It has now emerged that the military ambulance had an engine problem and broke down. Mr Mandela and his team of doctors from the department of defence, which handles the care of all former heads of state, reportedly waited for up to 40 minutes for a replacement vehicle.

A statement from President Jacob Zuma's office said all care was taken to ensure that Mandela was not adversely affected by the "unforeseen incident". "Doctors are satisfied that the former president suffered no harm during this period," Mac Maharaj, a spokesman for the presidency, said.

"The fully equipped military intensive care unit ambulance had a full complement of specialist medical staff including intensive care specialists and ICU nurses. The convoy also included two quick response vehicles." The statement added that Mandela was still in a "serious but stable condition" and appealed to the public and the media to continue to respect his privacy and that of his family. South Africans, themselves frequently victims of variable public service delivery, took to Twitter to express their disappointment at the news.

One, Palesa Marudu, wrote: "Like all of us, Mandela experienced service delivery SA style. Only Jacob Zuma is spared the inconvenience." The update was the first for nearly a week on the health of South Africa's first black president. Last weekend, Zuma said that while Mr Mandela's condition remained serious, he had made a "sustained recovery" over two days. The latest statement came following a series of reports that gave differing accounts of his condition. One, citing his grandson Ndaba, claimed he would return home "soon".

Thabo Mbeki, who succeeded Mandela as president, also told a local radio station that he was in "very close contact" with Mandela's family and he was "improving". "I don't think anybody should kind of entertain some wrong notion that Nelson Mandela is about to die tomorrow," he said. "He's not going to. I think we really need to feel comforted that we still have him with us now and will have him with us in future."

But another report by a US broadcaster claimed that Mandela's condition was far worse than suggested and that his family were discussing how long his intensive medical care should continue. The Sunday Telegraph understands that while Mr Mandela has been able to acknowledge and smile at his visiting family in the past week, his doctors are not optimistic about him making the full recovery hoped for by so many people all over the world.

"He is very, very sick, there's no denying that," said a source with knowledge of the situation. Meanwhile the White House confirmed yesterday that President Barack Obama may meet members of Mandela's family instead of the Nobel laureate himself, as was originally planned, when he visits South Africa next week with his family. Obama, who last met Mr Mandela soon after he was elected a senator in 2005, has described him as "one of my personal heroes".