At a press conference in Mumbai, Singh alleged that Kejriwal had information to expose Pawar but had concealed facts.
"Details of the larger irrigation scam were not brought out," Singh alleged.
Responding to Singh's remarks, IAC activist Manish Sisodia said they congratulate him on making these "revelations" and it is good if corrupt political bigshots are exposed.
"We don't exactly know why Y P Singh is saying so that we did not reveal documents against Sharad Pawar. He is a very good friend of ours. There is nothing like this.
"I think this issue should be confined to Sharad Pawar scam instead of taking it as Arvind Kejriwal vs Y P Singh war," Sisodia said.
A statement posted in the Facebook account of India Against Corruption alleged that Pawar has misused his position and has severe charges of graft against him.
"IAC has been saying this since long. Sharad Pawar was also one of the 15 ministers against whom Kejriwal, Sisodia and Gopal Rai were on fast for 10 days at Jantar Mantar from July 25.
"The charges against Sharad Pawar have once again been proved by Y P Singh. IAC congratulates Singh for his courage to speak up against such a powerful minister," it said.
Before Singh's press conference, Kejriwal said, "Singh is doing a good work and I respect him, why is he saying all of a sudden, I don't know."
Yesterday, Kejriwal had levelled fresh allegations against BJP chief Nitin Gadkari on irrigation scam and claimed that he had usurped agriculture land acquired for building a dam.
Sisodia asked people to put all details before the country.
"If everyone make such expose like Arvind Kejriwal and Y P Singh, good results will surely come as public has become aware nowadays," he added.
