The chairman of the House Intelligence Committee is blocking access to classified material from Rep. Randy "Duke" Cunningham and his staff following the lawmaker's admission he accepted $2.4 million in bribes.

Cunningham, R-Calif., announced his resignation from Congress Monday after entering a guilty plea to charges of corruption and tax evasion. The former congressman admitted that he accepted bribes from defense contractors who later received government contracts. On Wednesday, his resignation letter was received at the U.S. House of Representatives, making his departure official.

Rep. Pete Hoekstra, R-Mich., committee chairman, launched an internal probe to review what access Cunningham had that may link to the bribery charges. He said he wants committee attorneys to review Cunningham's dealings to determine if he acted improperly or if his actions influenced committee decisions.

Cunningham, who was in his eighth term of Congress and had been a member of the committee since 2001, also served this year as chairman of the subcommittee on terrorism and human intelligence. All members of the the committee are given access to classified material.

Hoekstra said he decided to look into the matter as a precautionary measure after Cunningham admitted to the charges, Capitol Hill sources told FOX News.

"He believes these concerns are incredibly serious, and that there has to be certainty that everything was done aboveboard on the Intelligence Committee," said Jamal Ware, committee spokesman. He said, however, that Hoekstra did not believe Cunningham had improperly influenced committee business.

Committee lawyers will review bills and programs from the panel that may show improper involvement by Cunningham, Ware said.

Hoekstra's request to deny access to intelligence will also apply to Cunningham's staffers, because congressional rules allow the former congressman's staffers to stay in their posts when a new member replaces the former lawmaker.

Earlier on Wednesday, House Minority Leader Nancy Pelosi urged House Speaker Dennis Hastert to create a bipartisan House committee to review Cunningham and his work with intelligence papers.

"The admissions of criminal conduct by former Congressman Duke Cunningham raise serious questions about his handling of highly classified information related to the national security of our country," Pelosi, D-Calif., wrote in a letter to Hastert, R-Ill. "The extent of Mr. Cunningham's misconduct has not been examined by the Congress to date, and we do not yet have a full disclosure of the breadth of his criminal activities by federal prosecutors."

Hoekstra said he also wants to meet with Justice Department officials about their investigation of Cunningham's dealings with defense contractors, Mitchell Wade of MZM Inc. and Brent Wilkes of ADCS Inc.

Lee Blalack, Cunningham's attorney, said his client would cooperate with any congressional inquiry, but only if federal prosecutors allow him.

Cunningham is free on his own recognizance as he awaits sentencing on Feb. 27. He faces up to 10 years in prison. In his guilty plea he admitted accepting cash, antiques, a Rolls Royce, mortgage payments on a mansion and boat, and other favors in return for helping the contractors gain valuable defense work.

According to his plea agreement, the following include some of the payments Cunningham received:

• $200,000 toward the purchase of his Arlington, Va., condominium;

• $140,000 to a third party for the "Duke-Stir" yacht, which was moved to his boat slip for his use;

• $16,867 to a marine services company for repairs to his own yacht, the "Kelly C";

• $12,000 paid to an antique store for three night stands, a leaded glass cabinet, a washstand, a buffet and four armoires;

• $6,632 paid to a furniture store for a leather sofa and a sleigh-style bed;

• $7,200 paid to an antique store for a circa 1850 Louis Phillipe period commode and a circa 1830 Restoration period commode;

• $13,500 toward the purchase of a Rolls-Royce;

• $17,889 for repairs to the Rolls-Royce;

• $11,393 paid to a moving company to ship his belongings from his Arlington condominium to his San Diego-area home;

• $2,081 paid to a Washington, D.C., hotel for his daughter's graduation party;

• $9,200 paid to a manufacturer for two Laser Shot shooting simulators; and

• $10,000 paid to various hotels, resorts and restaurants for his meals and entertainment expenses.

He also received hundreds of thousands of dollars in cash for a company he controlled.

FOX News' Jim Mills and The Associated Press contributed to this report.