"He (Singh) has put in his papers today (Wednesday) and it will come into effect from Dec 31," a spokesperson for Jaswant Singh told IANS.
Sources close to the former defence minister said that the leader wanted to announce his resignation publicly but it was leaked by members of the PAC.
BJP had asked Jaswant Singh to step down from the post of PAC's chief after he was expelled in August from the primary membership of the party following his book on Pakistan founder Mohammad Ali Jinnah.
Jaswant Singh declined to comply, prompting BJP members to boycott the panel's subsequent meetings in protest.
BJP had asked Jaswant Singh, who is member of Lok Sabha from Darjeeling constituency, to quit the parliamentary panel on grounds of morality.
The 22-member PAC committee scrutinises government spending. Jaswant Singh was appointed its chairperson when he was in the BJP.
