London, Dec 18: The Mercedes Formula One racing team is reportedly planning a top-secret test, expected to last for at least a week, for seven-time world champion Michael Schumacher before his sensational F1 comeback next season.

It was earlier said that Schumacher had agreed to a deal to race for Mercedes GP, and having lured him away from Ferrari, his new bosses are desperately trying to keep the event a secret.

Speculation on where it will be held includes Abu Dhabi, the stunning desert venue that staged the final round of the world championship in November, and Bahrain, which will stage the opening race of 2010, The Mirror reported.

Schumacher, mulling a return four years after he retired, is expected to test a car from the GP2 feeder series.

The 40-year-old is on a fitness drive after a neck problem ruled out a comeback for Ferrari last season.

He earned 30 million pounds a year in his F1 heyday with Ferrari, but driver salaries have since come down dramatically.

Mercedes has offered a seven million pound salary to Schumacher, which would be way off double champ Fernando Alonso, who is earning around 15 million pounds at Ferrari, and Lewis Hamilton, on 13 millions at McLaren.

But triple champ Niki Lauda said: “Money is not an issue for Michael. The question is whether he would want a new challenge.” (ANI)