"I would like to congratulate Abhishek and Aishwarya. I hope they make a cricket team," Salman told reporters at an event to launch a Blackberry application in Mumbai.
"I am happy for the Dadaji (Amitabh Bachchan)," he said.
Aishwarya began dating Salman in 1999 during the filming of Hum Dil De Chuke Sanam.
The couple officially separated in 2002.
On Tuesday night, Amitabh announced the pregnancy news on micro-blogging site Twitter.
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