A federal appeals court yesterday took a sterner stance toward the upcoming resentencing of disgraced lawyer Lynne Stewart, convicted of aiding her jailed terrorist client — saying it has “serious doubts” whether her sentence of just over two years in prison was sufficient.

The 2nd US Circuit Court of Appeals in Manhattan added new instructions for the judge who will resentence Stewart, 70, for letting blind terror sheik Omar Abdel-Rahman communicate with followers from jail.

The court said the judge should consider whether Stewart’s sentence should be increased because of her crime’s terror implications.