Michael Schumacher's manager has called a halt to production of memorabilia and merchandise celebrating the return of the seven-time world champion to Formula One.

According to Germany's Auto Bild, Willi Weber fears a repeat of 1997, when he spent a million euros on merchandise celebrating Schumacher's first title for Ferrari, when in fact Jacques Villeneuve pipped him at the post.

This time, the fear is that while Schumacher intends to fill the injured Felipe Massa's cockpit in Valencia and beyond, there are growing doubts about the health of his neck.

"As long as the return is not one hundred per cent for certain, we are producing nothing," said Weber.

It is rumored that Schumacher may even have fractured a bone when he hurt his neck in a motorcycle testing crash in February.

"It was a very bad accident," his spokeswoman Sabine Kehm told Sunday's edition of the Frankfurter Allgemeinen Sonntagszeitung, "but we are not going to talk about it in public."

It is a believed a decision about the 40-year-old's Valencia return will be made some time this week.

"Only when all the test results are available can we make a decision," said Dr Johannes Peil, of the Bad-Nauheim Sportklinic. "The last word will be Schumacher's," he added.

Refunds for tickets bought to witness Michael Schumacher's aborted Formula One return at Valencia will not be refunded, according to Auto Motor und Sport.

News of the seven time world champion's comeback triggered a spike in flagging sales for the Spanish street race, even though 30,000 of the available 75,000 Sunday tickets are still on the market.

Carlos Gracia, head of the Spanish motor racing federation, was present at Renault's race ban appeal hearing in Paris on Monday, but he denied the Court of Appeal ruled in the team's favor in order to prevent a disasterfor the Valencia event.

If the ban had stood, not only would Schumacher not have been in action, but also absent would have been the local favorite Fernando Alonso.

"One has nothing to do with the other," Gracia told the Spanish newspaper AS. "The Court of Appeal did its work with absolute independence and total autonomy."

Ferrari is still pushing hard to arrange a third Formula One car for Michael Schumacher to race in 2010.

With BMW and Toyota now departed, Renault thinking about following suit and the famous Italian team scornful of the sport's new entrants, Luca di Montezemolo has renewed his campaign to have the rules changed.

"This is perhaps an opportunity to have a third car for each team," the Ferrari president told Bild newspaper. "I will do everything I can. And naturally we are thinking of Michael Schumacher for our third car."

At the same time, Schumacher - despite calling off his return in Felipe Massa's car in August due to injury- is not ruling out making another bid to come back to the grid.

"Let's put it like this, I do not see a reason why I should confirm or rule out anything," the seven-time world champion told Gulf News.