The party has reportedly planned to make the formal announcement after a meeting of the parliamentary board at 4 pm on Friday.
Advani has told party president Rajnath Singh that he will oppose Modi's candidature for the prime ministerial post at the party's parliamentary board meeting.
"Sources now say that party patriarch LK Advani has told Rajnath that unlike Goa, he will attend the Parliamentary board meeting and register his protest on nominating Modi," reported CNN-IBN on Thursday.
Meanwhile, Singh on Thursday said a final call on announcing Modi as the party's prime ministerial candidate will be taken after talking to "everyone".
"We will decide on who will be our nominee after talking to everyone and reaching a consensus," Singh told media.
Advani has reportedly told Singh that announcing Modi as their prime ministerial candidate for the 2014 Lok Sabha elections will be a 'disaster'.
According to BJP sources, during Wednesday's meeting with Singh, Advani said the announcement on Modi will be a "disaster" and will "destroy the party's prospects" in 2014 polls.
But Modi enjoys support of many leaders too within the party.
BJP leader from Bihar Sushil Kumar Modi on Wednesday criticised Advani for reportedly opposing the anointment of the Gujarat Chief Minister as the prime ministerial candidate for 2014 elections.
"Adavaniji has failed to gauge the public mood.Advaniji himself declared Atalji as PM candidate now also he could have done the same forNamo (Narendra Modi)," Sushil Kumar Modi tweeted on Wednesday.
"If you don't agree with the public mood, it becomes very difficult to win elections," Sushil Modi told NDTV.
"You go on digging up the same Godhra issue in every election but you can't get the dividend of the same issue in each election," he told the channel on Thursday.
"The public, workers are not willing to accept anyone other than Narendra Modi. You can't impose anyone as PM or CM candidate," he said.
BJP's ideological mentor Rashtriya Swayamsevak Sangh (RSS) on Tuesday backed the Gujarat Chief Minister's candidature as the next Prime Minister of India.
"The nation needs a special change. It is clear who they want as their next Prime Minister," RSS spokesperson Ram Madhav told reporters.
Asked if he is referring to Modi, Madhav said: "The whole world knows who we are referring to, who has got the people's approval."
However, he said it is up to the BJP to take a final decision on the issue and make an official announcement.
--IBNS (Posted on 13-09-2013)