The ad will be produced by Shah Rukh's production company, Red Chillies, producer of his recent hit Main Hoon Na.
It will be directed by Main Hoon Na director Farah Khan.
Though the composer did not disclose the name of the car for which the ad is being created, it will most likely be the Hyundai Santro, of which SRK is brand ambassador.
When this correspondent visited Anu's home for an interview, Farah was sitting with a band of musicians and helping Anu give final touches to the score.
This is Anu's first ad assignment.
"I have never done this kind of work before," he says. "The ad world is finally seeing my work and I am being approached by a lot of people who want me to do ads for them," he says.
The music has been scored in three slots. One is for a 30 second ad, the second for a minute, the third for three minutes.
"The ad world is not different from our world," says the flamboyant composer. "I will love to do more of this in future."