Disgraced financier Bernard Madoff will not appeal his 150-year sentence for a fraud that unraveled overnight last December when Madoff confessed to his sons that nearly $65 billion he promised investors was safe was actually only worth a few hundred million dollars.

“We won’t be appealing the sentence,” Madoff’s lawyer, Ira Sorkin, said Thursday. He declined to say why the decision was made. Rebekah Carmichael, a prosecutor’s spokeswoman, declined to comment.

The 71-year-old Madoff was sentenced last week after admitting he bilked thousands of investors out of billions of dollars — an epic scheme that spanned the globe, according to a report released Thursday by a court-appointed trustee.

The report by trustee Irving Picard — responsible for identifying Madoff assets that could be used to compensate victims — said the search “has unearthed a labyrinth of interrelated international funds, institutions and entities of almost unparalleled complexity and breadth.”