DOVER, Del. (AP) — A federal judge in Delaware says creditors unhappy with Tribune Co.'s plan to exit bankruptcy protection must post a $1.5 billion bond if they want the plan to be put on hold while they appeal.

The judge approved the plan last month. But some creditors are challenging the settlement of legal claims stemming from Tribune's 2007 leveraged buyout and the treatment of certain bondholders under the plan.

The judge agreed Wednesday to put Tribune's plan on hold if those creditors post a bond to cover any potential costs to Tribune and other creditors. Tribune said last week that the company would suffer significant financial hardships if the plan is put on hold.

The judge refused a request by some creditors for permission to bypass a federal district court and take their challenge directly to a federal appeals court in Philadelphia.