CHICAGO — Federal prosecutors announced charges Tuesday against two Chicago men who they accuse of illegally lobbying U.S. lawmakers to lift sanctions against longtime Zimbabwe President Robert Mugabe and members of his regime in exchange for a promise of $3.4 million.

Prince Asiel Ben Israel, 72, and C. Gregory Turner, 71, tried to persuade unnamed U.S. state and federal lawmakers, including four from Illinois, to oppose the sanctions against the leaders of the southern African nation, according to the charges unsealed Tuesday in U.S. District Court in Chicago.

The complaint says the men met with Mugabe, Reserve Bank of Zimbabwe Gov. Gideon Gono and other officials "multiple times" in the U.S. and Africa, and allegedly agreed to lobby U.S. federal and state officials on Zimbabwe's behalf in exchange for the promised payments, which the defendants apparently weren't able to collect in full.

No lawmakers have been accused of wrongdoing, although the investigation is ongoing, the U.S. Attorney's Office in Chicago said in a news release. It's not illegal for public officials to meet with sanctioned Zimbabweans, but individuals cannot provide lobbying services to those subjected to U.S. sanctions, prosecutors said.

Mugabe's government has been under sanctions since 2003 for alleged democratic violations.

Ben Israel appeared in a federal courtroom in Chicago Tuesday, where the terms of his bond were changed to require him to remain in contact with the court's pretrial services department. His wife, Hattie Brown, also appeared in court, promising U.S. Magistrate Judge Arlander Keys that she would turn in her husband if he attempts to flee.

The complaint alleges that the defendants violated the International Emergency Economic Powers Act. The violation carries a maximum penalty of 20 years in prison and a $1 million fine.

Ben Israel's attorney, Viviana Ramirez, said Tuesday that it's too early to address the merits of the case. Turner, a Chicagoan, is believed to be currently living in Israel. A warrant has been issued for his arrest.

According to the complaint, Ben Israel and Turner began talking with Mugabe and other Zimbabwe leaders in early November 2008 regarding the influence they could exert to lift the sanctions originally imposed by President George W. Bush.

The defendants allegedly discussed with Mugabe, Gono and others their ties to several public officials who supposedly had close connections to then-President-elect Barack Obama.

The complaint states that Ben Israel and Turner engaged in public relations, political consulting and lobbying efforts and had a Nov. 26, 2008, "Consulting Agreement" that called for an initial payment of $90,000 and three subsequent equal installments of $1,105,000.

The defendants allegedly arranged for Ben Israel to travel to South Africa with two Illinois lawmakers — referred to as "Illinois State Senator A" and "Illinois State Representative A" in the complaint — in early December 2008. Travel records show the two lawmakers traveled to Israel, but did not return as scheduled and extended their overseas stay, the complaint states.

Three days after the lawmakers' return in mid-December, a scheduler for President-elect Obama's transition team sent an email to another transition team member stating that State Representative A "wants a phone call from (transition team officials) regarding a meeting he had last week in Zimbabwe. I am not sure who to pass this on to but it's the second time they have called."

The transition team forwarded the email to the FBI based on its concerns that the state representative may have violated sanctions by traveling to Zimbabwe, according to the complaint.

Obama has decided each year of his presidency to keep the Zimbabwe sanctions in place, most recently in March.

Mugabe, 89, has been president of Zimbabwe for 33 years. He was re-elected by a wide margin last week, although his political opponents say voting wasn't free or fair and was marred by widespread irregularities.