The condition of the multiple Formula One world champion Michael Schumacher was the subject of fresh concern on Thursday evening following a remark from his old Ferrari boss Luca di Montezemolo, who said: “I have news and unfortunately it is not good.”

The former Ferrari president, who said he was “always checking up on the driver”, was speaking to journalists in Milan, and added: “Michael was a great driver, and we experienced a long time together in both our personal and professional lives. But life is really strange. He was the most successful driver of Ferrari and in his career he had only one accident, in 1999. But unfortunately a fall in a ski accident has broken him.”

The news about Schumacher has not been good for more than two years. On 29 December 2013 he suffered severe head injuries in a freak skiing accident in France. He had been enjoying a holiday with his wife, Corinna, and children Mick and Gina Maria, in a villa owned by the family in Mirabel. He underwent emergency surgery after being airlifted from the mountain and spent months in a coma in hospital before being transferred to his home by Lake Geneva in September 2014.

There, he received intensive treatment from a team of therapists but there have been no encouraging official bulletins and it was widely believed that the German was becoming increasingly frail as he lost more and more weight.

There was some good news last month, with reports in the German magazine Bunte that he was walking again and moving his arm. A “friend” of the driver said: “Michael is very thin. But he can once again walk a little with the help of his therapists. He manages to make a couple of steps. And he can also raise an arm.” But an angry Sabine Kehm, Schumacher’s manager, denied this.

She said: “Unfortunately, we are forced by a recent press report to clarify that the assertion that Michael could move again is not true. Such speculation is irresponsible, because given the seriousness of his injuries, his privacy is very important for Michael. Unfortunately they also give false hopes to many involved people.”

A more accurate assessment, it seemed, came from the FIA president and former Ferrari team principal Jean Todt during November’s Mexican Grand Prix. Todt said: “I see Michael very often and Michael is still fighting. Michael is a close friend, his family is very close to me and I am very close to them as well. We must keep him fighting with the family.”

Todt’s worried words were in keeping with the general air of pessimism that has pervaded the world of Formula One for the past two years. Philippe Streiff, a friend of the driver, said in November 2014 that the former champion could not speak. He added: “It’s very difficult. Like me, he is in a wheelchair, paralysed. He has memory problems and speech problems.”

Schumacher’s records may never be broken. He won the world title on seven occasions and also won more races, 91, than any other driver. He won his first championship with Benetton in 1994, retaining his crown the following year. But it was with Ferrari that his driving assumed legendary status.

He won five successive titles before retiring in 2006. He was totally dominant in 2004, when he won 12 of the first 13 races. He finished with 13 wins, beating his record of 11 set in 2002.

He returned to Formula One in 2010, when he drove for Mercedes alongside Nico Rosberg. But in his three seasons with the Silver Arrows he could not recapture old glories, with a best finish of third at the 2012 European Grand Prix in Valencia.