Aishwarya pregnant, tweets Big B

Bollywood's star couple--Abhishek Bachchan and Aishwarya Rai--are expecting their first baby. Superstar Amitabh Bachchan, the expectant granddad and Abhishek's father, spilled the beans on the microblogging site Twitter tonight to say his daughter-in-law Aishwarya is pregnant.

"NEWS NEWS NEWS !! I AM GOING TO BECOME A GRANDFATHER .. AISHWARYA EXPECTING .. SO HAPPY AND THRILLED !!!," Bachchan Sr tweeted.

The baby will be the couple's first child. Abhishek,35, and Aishwarya, 37, tied the knot on April 20, 2007.

Aishwarya has not personally confirmed she is pregnant.But Archana Sadanand, the publicist for the former Miss World, said there is nothing more to add other than what Amitabh had said.