Advani, who is MP from Gandhinagar, and Jaitley, Rajya Sabha MP from the state, will leave for Ahmedabad on Saturday morning to attend the fast to be undertaken by Modi.
Other Central leaders who will attend the fast are BJP General Secretary and Chief Spokesperson Ravi Shankar Prasad, spokesperson and MP Shahnawaz Hussain and general secretary Vijay Goel.
Modi is undertaking the fast days after the Supreme Court verdict asking the Special Investigation Team (SIT) to file a final report or a chargesheet to be heard in a lower court in Gujarat in the Gulbarga Society riots case.
Central leaders Ananth Kumar and Balbir Punj (who is in-charge of Gujarat) are also likely to attend Modi''s fast, party sources said. They are away in Singapore to participate in a seminar organised by Institute of South Asian Studies (ISAS).
After the Supreme Court order, the buzz is that this paves the way for Modi to play a larger role in the BJP at the national level. This includes Modi becoming the next party president or even be declared the next Prime Ministerial candidate of the party.