Bernard Madoff, on his way to Manhattan Federal Court on March 12 where he pleaded guilty to one of the biggest Wall Street frauds in U.S. history, was being held in a detention centre in Manhattan. (Louis Lanzano/Associated Press)

The lawyer for Bernie Madoff said Thursday that the disgraced financier won't appeal the 150-year prison sentence handed to him last week in a New York City courtroom.

Madoff's lawyer, Ira Sorkin, declined to say why they won't appeal the prison term.

Madoff was sentenced on June 29 for fleecing hundreds of investors out of tens of billions of dollars in a massive Ponzi scheme.

Madoff, 71, has been held in a Manhattan federal detention centre since March, when he pleaded guilty to securities fraud and other charges.

There's no decision yet on where Madoff will serve his sentence.

U.S. District Judge Denny Chin called the fraud "staggering," adding that "the breach of trust was massive."

At the time of Madoff's arrest late last year, fictitious account statements showed thousands of clients had investments worth $65 billion U.S. But investigators said he never traded securities, and instead used money from new investors to pay returns to existing clients.

Madoff was ordered to forfeit about $170 billion on June 26 — the amount prosecutors said flowed through the main account used to operate the scheme — not an actual amount of assets held. The government will probably only be able to recoup a fraction of it.

Prosecutors said the total losses, which span decades, haven't been calculated. But 1,341 accounts opened since December 1995 alone suffered losses of $13.2 billion, they said.