Michael Schumacher faces a "long fight" for recovery on the first anniversary of his skiing accident.
The former Formula One driver suffered severe head injuries in a ski accident in Meribel in the French Alps on 29 December 2013. He emerged from an induced coma in June, and left hospital in September.
Schumacher's manager Sabine Kehm said on Sunday: "We need a long time. It's going to be a long time and a hard fight.
"He is making progress appropriate to the severity of the situation," she added, reiterating a statement she made a month ago.
Her comments cast doubts over a newspaper report that said he was making cognitive progress.
In an interview with Le Parisien on Sunday, Philippe Streiff, another former F1 driver, said Schumacher "had yet to recover the power of speech" but was "nevertheless starting to recognise those close to him".
Streiff, described by the newspaper as a long-time friend, said he got the information from contact with Schumacher's wife Corinne, and his surgeon, Gerard Saillant, whom he knows as a result of his own racing accident in 1989.
He said Schumacher, who will be 46 on 3 January, had "very limited" movement but was working on sitting upright, and that "long term... he could hope one day to walk with crutches".
Kehm said Streiff was not a close friend of Schumacher and that his claims to have had contact with the two people named were "factually wrong".
"I cannot confirm that," she said. "I can only confirm that I do not know where Mr. Streiff has his information from because he has no contact with us and he never has."
LIFE-CHANGING FALL
Michael Schumacher's fate has gripped the world for a year following his tragic skiing accident.
Just as in previous years, he wanted to spend a few days skiing to celebrate the new year and his birthday with friends. But a fall at the Meribel ski resort changed his life and that of his family forever; even a year after the tragic accident on 29 December 2013, it remains unclear whether Schumacher will ever recover enough to lead any semblance of a normal life.
"It is not possible to give any kind of reliable prognosis," Kehm said recently. "It simply isn't possible in this situation."
Schumacher hit his head on a rock while skiing and spent the next days in a critical condition in a Grenoble hospital, followed by months in an induced coma.
His helmet was destroyed in the fall and the seriousness of his condition only became apparent the following day when he was transferred to the University Clinic Hospital in Grenoble.
The expressions on the faces of the doctors treating Schumacher spoke volumes. His condition was described as "extremely critical" as the world learned that the seven-times world champion had sustained multiple brain injuries.
Schumacher's fight for life unleashed deep emotions worldwide with television programming regularly interrupted to give updates on his condition.
The media circus that developed around Schumacher's fight for life led wife Corinna to issue a written statement a week later, calling for the driver's medical team and family to be left in peace so they could deal with the situation.
Schumacher was still fighting for his life on January 3, 2014, when he celebrated his 45th birthday, with the tragedy casting a shadow over the start of tests for the new F1 season.
"We are praying, wishing and hoping that a miracle takes place so that he wakes up the same person he once was," said compatriot and friend Sebastian Vettel at the end of January.
BAMBI AWARD
More than 10 months later, on the 20th anniversary of Schumacher claiming his first F1 title, Vettel was on hand to present the Millennium-Bambi award to Schumacher's wife in recognition of the driver's excellent services and for inspiring his countrymen.
"It's my friendship with him that makes me so happy and proud, but also so sad," said Vettel. "I had so wished that we would be able to give you this award personally."
Schumacher's legion of fans is still writing letters as well as sending get-well wishes on Twitter and Facebook. The sport of Formula 1 is also still thinking of the man who enjoyed 91 race wins in a stellar career.
When Lewis Hamilton secured the 2014 Drivers' championship in Abu Dhabi, Daimler boss Dieter Zetsche remembered the German legend when looking back on a memorable season for his team.
"We should not forget the contribution Michael made to this success," he said.
Schumacher drove for Mercedes for three years from 2010 to 2013, offering his vast experience just as he had previously done for the Ferrari research team.
In a uniquely successful career, Schumacher secured 68 pole positions on his way to seven world championship crowns.
He suffered his worst racing accident in 1999, when he broke his leg at Silverstone. Schumacher also suffered neck injuries in a motorcycle accident in Cartagena 10 years later, forcing him to call off a comeback with Ferrari as a replacement driver for the injured Felipe Massa.
Schumacher has continued his rehabilitation at home since September and his family have made clear from the beginning that no details will be revealed about his condition.
She also confirmed recently that virtually all of Schumacher's sponsors have remained loyal to the driver, even a year after his tragic accident.
"Our concept was always to work together personally on a partnership and friendship level," Kehm said. "This togetherness is showing itself now."
Reuters/Sapa-dpa