GENEVA: Former world champion Michael Schumacher said Wednesday he was too disappointed at present to contemplate a return to Formula One later this year or in 2010.

Schumacher on Tuesday announced that he had abandoned plans to replace injured Ferrari driver Felipe Massa at the European Grand Prix in Valencia on August 23 due to the consequences of a neck injury.

"Speculation in this business is pretty natural, the fact is that I'm disappointed I'm not able to do what I looked forward to do ... that's how I feel for now," a downbeat Schumacher said after being asked about suggestions of a comeback at a following race in Monza or next season.

The 40-year-old German, who won the world title seven times before retiring in 2006, had been primed to replace Massa in the Ferrari team for the race in Spain following the Brazilian's high speed crash last month.

But he injured his neck in a motorcycle accident in February and medical exams after test runs in a Ferrari at a circuit in Italy in recent weeks showed that Schumacher had not recovered enough to withstand the strains of motor racing.

"The consequences of the accident were the worst Michael has had in his career," Schumacher's doctor, Johannes Peil, revealed at a press conference here.

Schumacher sustained fractures to the base of the head, vertebra and a rib in the motorcycle accident on a racing circuit, although most had fully healed, Peil added.

Ferrari announced that the team's test driver Luca Badoer would take the place for the European Grand Prix.