Skilling was convicted in 2006 on charges including conspiracy and securities fraud in relation to the 2001 collapse of the one-time energy trading giant Enron. The 58-year-old is now serving a 24-year jail term.

Skilling attorney Daniel Petrocelli has asked a judge for more time to file a "motion for a new trial based on newly discovered evidence", according to court filings last week in Houston federal court.

The court papers did not detail the new evidence.

U.S. District Judge Sims Lake on Monday ordered a May 25 hearing on the motion.

Skilling as chief executive led Enron's transformation from a sleepy natural gas pipeline company into a global energy trading powerhouse, which disintegrated in bankruptcy in 2001.

After Skilling was convicted, his case was heard by the U.S. Supreme Court, which invalidated one theory underpinning the conspiracy conviction, and instructed an appeals court to review the case again.

But the U.S. 5th Circuit Court of Appeals in New Orleans later found any error committed by the trial judge was "harmless."

The case is U.S. v. Skilling, U.S. District Court for the Southern District of Texas, No 04-0025.

(Reporting By Basil Katz; Editing by Michael Perry)

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