By ESPNSTAR.com staff
Schumacher is without a team following news of Mercedes' decision to replace him with McLaren's Lewis Hamilton for the forthcoming season. This has led to speculation that the legendary German driver could quit Formula 1 for a second time as it's uncertain if he still has any interest in competitive racing after three poor seasons.
Kehm revealed that Schumacher also had the option to sign an extension to his contract but instead he chose to delay the decision earlier in the season. It was this hesitation that prompted Mercedes to act quickly and sign on Hamilton with the Briton set to receive a bumper contract worth £15million per year.
"Michael didn't stay at Mercedes because he wasn't sure he wanted to drive and that didn't change over time," Kehm told BBC Sport.
"[He] would have been able to sign if he had wanted to earlier in the summer."
It is believed that Sauber could sign the 43-year-old and Kehm was spotted paying a visit to the team's paddock during the Singapore Grand Prix. But she denied that any discussion of Schumacher joining the team in either a racing or a mentoring capacity took place during the event.
"It's true I was at Sauber," she said. "I have been there quite often. I have known them for years. But that doesn't mean anything more than I'm regularly there."
But team principal Peter Sauber told Auto Motor und Sport during the Singapore race that he would sign Schumacher "immediately" if he became available.
Sauber refused to comment on the speculation and have insisted that they are happy with the existing duo of Kamui Kobayashi and Sergio Pérez.
Ferrari, Williams amd Lotus are the other names that have been mentioned but the German driver is expected to make an announcement only towards the end of the season.
Schumacher has only achieved 43 points in the current season and has one podium finish to his name since 2009.