The British government on Wednesday refused parole to ailing "Great Train Robber" Ronnie Biggs, saying he is an unrepentant criminal and must remain in jail.

Justice Secretary Jack Straw said Biggs, who is 79 and in failing health, cannot be freed because he does not regret his crimes.

Biggs was part of a gang that robbed a Glasgow-to-London mail train in August 1963, in what was called the "heist of the century." The robbery netted 2.6 million pounds — worth more than $50 million today.

Most of the gang was soon rounded up. Biggs was sentenced to 30 years in jail but escaped from prison in 1965 and fled to Brazil, where he made a living from his notoriety, regaling journalists and tourists with stories of his exploits and even recording with punk band The Sex Pistols.

In 2001, he voluntarily returned to Britain, surrendered to police and was sent back to jail.

His lawyers sought to have him released, arguing that his age and severe health problems mean he is no longer a threat.

He becomes eligible for parole on Friday, when he will have served a total of 10 years of his 30-year sentence. But Straw said he was overruling a Parole Board recommendation that Biggs be freed.

He said Biggs "chose to serve only one year of a 30 year sentence before he took the personal decision to commit another offense and escape from prison, avoiding capture by traveling abroad for 35 years whilst outrageously courting the media."

"Had he complied with his sentence, he would have been a free man many years ago," Straw said.

Biggs, who has suffered a series of strokes and other health problems, is currently being treated in a hospital for a broken hip and suspected pneumonia.