Democratic candidate for governor Roy Barnes isn't going to let voters forget that his main opponent in Georgia's gubernatorial race has not yet made his tax returns available for public review.

In an advertisement released Friday, Barnes' campaign claims Deal, who nearly three weeks ago secured the Republican nomination for governor, is "hiding something" about his financial past.

"We think it's in his income tax records," a male voice on the advertisement says. "But they're locked up tight."

A spokesman for Deal refutes the claim, and says Deal's accountants are working on getting his tax information ready for release.

Barnes, a former governor, made 25 years of tax returns available online in early May. He has repeatedly called on other gubernatorial candidates to do the same.

Barnes faces Deal and Libertarian John Monds in November's election.

In an open letter Barnes wrote in late May, the Democrat cited a belief that "those seeking public office should be committed to the principles of open government and full disclosure."

And Deal's campaign says it plans to release the tax information — just not on Barnes' schedule.

"We're not working on Roy Barnes' time line," Deal's director of communications Brian Robinson said.

"... Nathan Deal has paid his taxes in full, and we aren't going to make decisions based on Roy Barnes' TV commercials."

The holdup, according to Robinson, is Deal's 2009 tax return. Deal has still not filed last year's taxes. The former congressman was granted an extension and is awaiting information from his bank to complete the return, Robinson said.

The information will be ready "any day now," Robinson said.

"As soon as those are completed and filed, it will all be (released) together," Robinson said. "That's been the last element."

But Barnes' camp questioned Deal's hesitation, calling the Republican candidate "too unsteady for the job" of governor.

"All that is required to release your personal and corporate tax returns is that you make a few copies — you don't need accountants or attorneys," said Emil Runge, a Barnes spokesman. "Of course, if you are hiding from your record of back-room deals and ethics investigations, you may need professional assistance."

Deal's camp insists, however, that ethics has nothing to do with why the information has not been released.

Robinson said Deal has paid his taxes in full and even claims Deal "overpaid taxes most years."

"(Deal) has nothing to hide," Robinson said. "... I don't know what magic information they think is out there."