ATHENS--Greece's government hopes to sell off state-owned gambling monopoly OPAP SA (OPAP.AT) by the end of the year or early January, a senior government official said Thursday, a move that would represent a significant step forward for the country's moribund privatization program.

"There are four consortia made up of Greeks and foreigners that have expressed an interest in the OPAP tender," the official said. "By the end of December, beginning of January the sale should be completed."

The company, with a market capitalization of about 2 billion euros ($ billion), is seen as one of the crown jewels of Greece's privatization program. The country's privatization agency plans to sell a 29% stake in OPAP, but that sale had been held up by concerns from the European Commission's competition agency over Greece's differential tax and regulatory treatment of OPAP.

Greece said this week that it was effectively abolishing its preferential tax treatment for the company, something that will weigh on future earnings but should clear the way for the company's privatization.

Also Thursday, a separate legal opinion by an adviser to the European Union's top court, suggested that the disputed monopoly status of OPAP should be decided by Greek courts, rather than the European Court of Justice. The opinion is seen as positive for the company and helped push its shares higher during intra-day trade before closing 0.2% lower at EUR4.3 on profit-taking.

Write to Nektaria Stamouli at nektaria.stamouli@dowjones.com and Alkman Granitsas at alkman.granitsas@dowjones.com

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