CHICAGO (AP) -- Federal officials say in a legal brief filed Monday that there is no reason why former Governor George Ryan should not start serving his six-and-a-half-year prison sentence.

The officials argue that Ryan received a fair trial and should not be allowed to remain free on bail while appealing his corruption conviction.

The 73-year-old Ryan is due to report Wednesday to the federal correctional center at Oxford, Wisconsin.

Ryan and co-defendant Larry Warner, who also is seeking bail, have remained free on bond since their April 2006 convictions.

Their last, slender hope of postponing the start of their prison sentences is a plea for bail to Supreme Court Justice John Paul Stevens.

Stevens gave the U.S. solicitor general's office until Monday afternoon to come up with a reply to the request for a fresh bond.

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