The Hill reported that the Clinton campaign took umbrage with the Illinois senator pressing for Clinton's 2008 income tax returns.
"I, for one, do not believe that imitating Ken Starr is a way to win a Democratic primary for the presidency," Wolfson was quoted as saying. "Over 20 years of the Clintons' tax returns are part of the public record."
Clinton has said she would release her IRS filings "on or about" April 15, ahead of the April 22 Pennsylvania primary, Wolfson said.
The Obama campaign shot back, saying Clinton, who made an opponent's failure to release his tax returns a campaign issue in her Senate race, is holding herself to a different standard.
"It is absurd that after weeks of badgering the media to 'vet' Senator Obama, the Clinton campaign believes that they should be held to an entirely different standard," Obama spokesman Bill Burton said.