A government witness claims political fundraiser Antoin "Tony" Rezko discussed efforts among high-ranking Republicans, including Karl Rove, to have Chicago's U.S. attorney fired, a federal prosecutor said Wednesday.

Rove, then-White House political director, and Republican national committeeman Robert Kjellander were among those mentioned in the alleged 2004 conversations as being involved in the effort, prosecutor Carrie E. Hamilton said.

The witness, Hamilton said, is former Illinois Finance Authority executive director Ali Ata, who on Tuesday pleaded guilty to tax fraud and lying to an FBI agent about Rezko's role in getting him his state job.

On Wednesday, Hamilton told Judge Amy J. St. Eve that Ata "had conversations with Mr. Rezko about the fact that Mr. Kjellander was working with Karl Rove to have (U.S. Attorney Patrick Fitzgerald) removed."

"Mr. Rezko's explanation, according to Mr. Ata, is that Mr. Kjellander is working with Mr. Rove to have Mr. Fitzgerald removed so that someone else can come in to the U.S. attorney's office and individuals who have been cooperating in this investigation with be dealt with differently," Hamilton said.

She did not give further details and federal officials declined to say more.

Hamilton made the statements in telling St. Eve that federal prosecutors hope to put Ata on the witness stand at Rezko's trial. But as Hamilton described it, Ata's testimony would most likely be thirdhand and St. Eve did not immediately rule on whether she would permit the jury to hear it.

Rove's attorney, Robert Luskin, said Rove and Kjellander have been friends since college, but Rove does not remember Kjellander ever talking to him about Fitzgerald.

"He does not recall Kjellander speaking to him about Pat Fitzgerald and is certain he never spoke to anyone at the White House about removing Fitzgerald," Luskin said Wednesday, adding that Rove has never been contacted by the U.S. attorney's office about the alleged conversations.

A telephone message seeking comment was left at Kjellander's lobbying office, Springfield Consulting Group, in Springfield. He is a former treasurer of the Republican National Committee.

Prosecutors also had sought Wednesday to ask attorney Steven Loren, who has been on the witness stand for most of this week, about what sounded like talk of a similar plan.

St. Eve described it as a conversation between Loren and Springfield lobbyist-millionaire William Cellini "regarding attempts to conceal the conspiracy."

"Namely, his purported statements that they would have Mr. Fitzgerald removed," St. Eve said. But she ruled Loren could not be asked about such statements, saying they were outside the scope of the Rezko case.

Neither federal prosecutors nor defense attorneys would divulge any more particulars concerning the alleged Loren-Cellini conversation.

Loren was outside counsel to the Illinois Teachers Retirement System, the $40 billion state fund that pays the pensions of retired downstate and suburban school teachers.

Rezko is charged with scheming to pressure kickbacks out of money management firms wanting to invest TRS assets. He also is charged with scheming with attorney Stuart P. Levine to split a $1.5 million bribe from a contractor wanting state approval to construct a hospital in the McHenry County suburb of Crystal Lake.

Levine sat on the state boards that made both decisions.

Hamilton's comments regarding Ata's conversations marked the week's second bombshell linked to Rezko's trial.

The first came Tuesday when Ata said in a signed plea agreement with federal prosecutors that Gov. Rod Blagojevich was on hand when Ata gave Rezko a $25,000 check for the Blagojevich campaign. Blagojevich immediately asked Rezko if he had discussed the possibility of a job on the state payroll for Ata, according the plea agreement.

Former U.S. Sen. Peter Fitzgerald, R-Ill., nominated Patrick Fitzgerald — no relation to the former senator — for U.S. attorney. He said at the time he wanted someone who would be independent in conducting investigations of Illinois' endemic corruption.

Since coming to Chicago, the New Yorker has sent former Gov. George Ryan and a number of other politicians to federal prison on corruption charges, while the Rezko case has provided numerous political black eyes for the incumbent Blagojevich.

Fitzgerald also was appointed the special prosecutor for Washington's CIA leak investigation in which I. Lewis "Scooter" Libby was convicted of perjury and obstruction of justice.

Luskin, who said he talked to Rove after his name came up in Rezko's trial Wednesday, said because Rove was a subject of that investigation, Rove "would have been especially sensitive to doing or saying anything that would appear to be interfering with Fitzgerald's independence."