In his latest remarks, Sinha said in an interview to a news channel that if popularity was the yardstick for choosing a leader, then actor Amitabh Bachchan should become the President of India.
The above comment was a jibe at BJP President Rajnath Singh who has kept reiterating that Modi was the most popular leader in the country.
At a time when the party is said to be considering whether to name Modi as its Prime Ministerial candidate, Sinha's comments have come as something of an embarrassment.
Sinha even said that senior leader LK Advani was the one best-suited for the PM's post. Asked about Sinha's latest salvo, BJP spokesperson Meenakshi Lekhi was cautious in her reaction.
"Our party president is aware of these comments and he will take cognisance. I am not authorised to speak on the issue," she said.
When pressed for a reaction, she said, "Please ignore Sinha".
Sinha, a former Cabinet minister and the sitting MP from Patna Saheb, had earlier praised Bihar Chief Minister Nitish Kumar as "PM material".
Kumar's JD(U) had recently walked out of NDA in protest against Modi's elevation as BJP's poll campaign chief.
Party sources said Sinha is apprehensive that BJP may not give him a Lok Sabha ticket in the forthcoming elections as he has not worked in his constituency and was not accessible to the locals.
There are murmurs that Sinha may shift to JD(U) were BJP to deny him a ticket and was thus preparing the ground for such a move through these comments.