Former Qwest Communications International Inc Chief Executive Joseph Nacchio on Friday asked a U.S. court to let him stay free on bail while he appeals his insider trading conviction, just over two weeks before the day he is set to report to prison.

In a court filing to the 10th U.S. Circuit Court of Appeals, Nacchio's attorneys said they planned to petition the U.S. Supreme Court to review the case within three weeks.

But some legal experts said the convicted insider trader was unlikely to be able to forestall the start of his jail term on March 23.

Nacchio -- convicted in 2007 in what was considered an important victory in government efforts to crack down on corporate chieftains who profited while their companies suffered -- was not a flight risk, his lawyers argued in a filing.

The motion to continue his release on bail comes a day after Nacchio's attorneys sought a new trial at a U.S. District Court in Denver, citing new evidence unearthed in a civil case brought by government regulators against Nacchio and other former Qwest executives.

The odds are against getting the Supreme Court...(or) that the motion for a new trial would be granted, said Jay Brown, a professor of corporate and securities law at the University of Denver.

Brown, who attended the criminal trial, said the Supreme Court takes few cases presented to it, and that in the new trial motion, Nacchio's lawyers would have to show that his right to a fair trial was violated -- a very high standard of proof.

Nacchio has requested a new trial based on new evidence not available at his 2007 trial, and now also is asking the U.S. Supreme Court to review the issue of whether an expert defense witness was improperly excluded from testifying, his attorneys said in a court filing on Friday.

But the case, which has see-sawed in favor of and against Nacchio over the past two years, appeared to be coming to a close, legal experts said.

This week, he was ordered to report to a minimum-security prison in Pennsylvania on March 23 to begin serving his six-year sentence.

TWISTS AND TURNS

Nacchio was convicted in 2007 in Denver federal court of selling $52 million in Qwest stock after company insiders warned him that that the regional telephone carrier would not meet its publicly stated revenue goals.

A three-judge appellate panel overturned his conviction last year, then nine judges of the 10th U.S. Circuit Court of Appeals reinstated his conviction just last month.

Denver defense attorney and legal analyst Scott Robinson, who also followed the case, said Nacchio, 59, stood a better chance of the Supreme Court hearing his case than in his bid for a new trial.

Nacchio's lawyers asked for a new trial based on evidence gleaned from a deposition in a civil fraud case filed by the U.S. Securities and Exchange Commission against Nacchio and former Qwest executives.

His lawyers said that the new information came from the company's former chief financial officer, who revealed that she had advised Nacchio of a smaller risk of Qwest missing its year-end revenue targets for 2001 than the risk that prosecutors had presented to the Colorado federal jury that convicted him.

The difference of a few percentage points in revenue may not matter when he sold $52 million in stock in a three or four week period, Robinson said.

However, Robinson said the narrow 5-4 decision by the appellate court to reinstate the conviction, and the exclusion of the defense witness, may persuade the high court to take another look at the case.

Admission of testimony from expert defense witnesses is a hot Supreme Court issue, he said.

(Editing by Leslie Gevirtz; editing by Carol Bishopric)