Very sad moment: Schumacher

The German, still suffering from pain after a motorcycle accident earlier this year, refused to discuss returning to the sport in the future and said danger was part of his personality.

"This is a very sad moment for myself," the German told a news conference on Wednesday. "It's possibly one of the toughest moments I have faced in my career.

Schumacher, who suffered fractures around the head and neck in the accident in February, had been expected to make his return at the European GP in Valencia on August 23.

Ferrari have instead given the seat to experienced test driver Luca Badoer. "We all know motorbikes have an element of danger but that is part of my nature, that is what I am. I jump out of planes, I ride motorbikes, I drive Formula One cars," said Schumacher. "Now I am disappointed I did it because it has stopped me from doing what I wanted to do."

Schumacher said that he found it easy to regain his fitness and that driving a Formula One car felt natural. But the pain began to appear during a private F1 day at Mugello last week.

"Getting into the car and driving the car was pretty natural," he said. "I didn't find any problems in adapting to the sport but I found the pain around the neck was pretty tough, especially over bumps. We did everything... possible but it didn't work out.”

Badoer said he was up to the challenge. "I have prepared myself to be ready under any circumstances just as I've been doing in previous years," he said. “I've been in this business for quite a while. After Felipe's accident (in Hungary last month) I intensified my programme.”