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By Andrew Quinn

WASHINGTON, Dec 23 (Reuters) - U.S. President-elect Barack Obama and a top aide have been interviewed by prosecutors investigating Illinois Gov. Rod Blagojevich, but an internal report released on Tuesday cleared them of any wrongdoing.

Blagojevich is mired in a corruption investigation that has left Obama's transition team scrambling to distance the incoming president from the scandal-tarred governor.

Among the charges the governor faces is the accusation that he tried to sell Obama's recently vacated Senate seat. He has denied the charges and refused to resign from his job.

The report released on Tuesday said Obama, his chief of staff Rahm Emanuel and close friend Valerie Jarrett, who had initially expressed interest in filling the seat, had been interviewed separately by the U.S. Attorney's office last week as part of their criminal investigation into Blagojevich.

The U.S. Attorney's office, in announcing the charges against Blagojevich this month, said Obama was in no way implicated. The internal report said Obama had had no contact or communication with Blagojevich or members of his staff about his Senate seat.

The report, which detailed contacts between Obama staffers and employees in Blagojevich's office, concluded there was no indication that any "quid pro quo" arrangement over the job had been suggested or considered by any Obama staffers.

"My inquiry determined that there was nothing at all inappropriate about those conversations," incoming White House attorney Greg Craig said on a conference call with reporters.