Missouri Attorney General Chris Koster's office has appealed the stay of execution for convicted killer Allen Nicklasson, calling the federal appeals court ruling "an abuse of discretion."

A three-judge panel of the 8th U.S. Circuit Court of Appeals granted the stay on Monday. Nicklasson was scheduled to be put to death at 12:01 a.m. on Wednesday for killing businessman Richard Drummond, who was fatally shot after stopping to help Nicklasson and two other men when their car broke down nearly two decades ago.

Late Monday, Koster's office asked for a hearing before the full 8th Circuit in an effort to carry out the execution as scheduled, but no decision had been made on that appeal by midday Tuesday.

The appeals court panel voted 2-1 to grant the stay, citing concerns about ineffective counsel at Nicklasson's trial and sentencing in 1996. Koster's appeal said the panel's "one-sentence order was an abuse of discretion because Nicklasson's claims have no significant possibility of success on the merits."

Nanci Gonder, a spokeswoman for Koster, said it wasn't clear when the appeals court would decide whether or not to take up the appeal. Nicklasson's attorney, Jennifer Herndon, did not respond to messages seeking comment Tuesday but has also asked the Missouri Supreme Court and Gov. Jay Nixon to intervene.