Blockbuster Inc. , which filed for bankruptcy last year, is preparing to put itself up for sale after creditors disagreed on plans to give the chain more cash, the Wall Street Journal reported on Thursday, citing unnamed sources.

Blockbuster now plans to seek buyers, the newspaper reported, saying that investor Carl Icahn and a consortium led by hedge-fund Monarch Alternative Capital are the leading contenders.

A spokesman for Blockbuster declined to comment.

Blockbuster shares were up 12.8 percent at 11 cents on the pink sheets.

(Reporting by Caroline Humer, editing by Gerald E. McCormick)