London  - Seriously ill British train robber Ronnie Biggs is seeking parole ahead of his 80th birthday, according to media reports quoting his son Sunday.

His request is to be decided at a parole board meeting on Thursday, the reports said.

"We are hopeful that he will be freed but we're trying not to count on the egg before it leaves the chicken," Biggs' son Michael was quoted by the BBC as saying. He gave July 3 as the planned release date.

Biggs, who earned notoriety for his involvement in the daring 2.6- million-pound mail train heist by a 15-member gang Britain in 1963, has been serving time at Norwich prison in eastern England.

He was initially sentenced to 30 years but escaped from prison and fled the country, evading capture for over three decades and returning to Britain voluntarily only in 2001.

Biggs turns 80 on August 8, 46 years to the day that he and his gang staged what became known as the Great Train Robbery. (dpa)