CHICAGO - A former top aide to Rod Blagojevich testified Thursday that the then-governor said he had a deal to appoint a state legislator to Barack Obama's U.S. Senate seat in exchange for letting a veto of ethics legislation stand.

Alonzo Monk testified that Blagojevich was worried the legislation would hurt his ability to raise funds because it banned people with state contracts of $50,000 or more from donating to the campaigns of politicians who administered them.

Blagojevich, who had campaigned by saying he would bring a new era of ethics in state government, had complained that the bill unfairly targeted the governor's office. It had passed both houses without a single no vote before his veto.

Monk quoted Blagojevich as saying former State Senate President Emil Jones agreed to the alleged deal. But Jones called for the vote, which passed just before Obama was elected president. The override vote might not have occurred had Obama not urged Jones, his mentor, to call his chamber to action.

Jones did not immediately respond to a message at his business.

Prosecutors began playing wiretap recordings Thursday, starting with one that includes a sometimes-agitated, audibly upset Blagojevich talking about fund-raising goals with Monk. They spoke about the need to pull in contributions before the ethics law kicked in. Monk acknowledged that it was Monk and Blagojevich on the tape.

Blagojevich has pleaded not guilty to trying to profit from his power to fill the Senate seat and squeezing people for campaign contributions. He could face up to 415 years in prison, though a judge would consider many factors.

Monk has pleaded guilty to scheming to pressure a racetrack owner for a contribution.

Earlier Thursday, Monk told jurors that Blagojevich drew his hand across his throat in a slashing gesture to signal that he did not want anyone told about alleged moneymaking plans involving his power as governor.

Monk said the governor gave the signal when they were alone in his campaign office in 2007 or 2008, indicating that if anyone asked about the alleged plans, he should tell them nothing.