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BATON ROUGE, La. - Mitt Romney said this morning that he would release only two years of tax returns despite increasing pressure from both Democrats and Republicans to release more, saying he was already doing more than what the law requires and is following the precedent set most recently by Sen. John McCain.

"John McCain ran for president and released two years of tax returns," Romney said during an interview today on "Fox and Friends." "John Kerry ran for president, and you know his wife, who has hundreds of millions of dollars, she never released her tax returns [and] somehow this wasn't an issue."

"The Obama people keep on wanting more and more and more, more things to pick through," said Romney, suggesting he didn't want to provide more material for the president's research team to filter through and use in what Romney called "dishonest" attacks.

Romney has said since April that he would release only two years of tax returns - his 2010 return, which is already public, and his 2011 return, as soon as it's ready. He filed for an extension on his 2011 filing, and his campaign said at the time that he would release it before mid-October, although that timeline could be changing, although a campaign source tells ABC News the release could now come before Labor Day.

The suggestion that Mitt Romney will release the 2011 returns earlier than expected - "in the next month or so," the source said - comes as the candidate faces a barrage of criticism from even many in his own party for not disclosing more information about his substantial wealth. Romney's father George released 12 years of returns as a presidential candidate in 1968. But Mitt Romney has suggested that he'd rather take the hit for not being transparent than reveal more information about his complex financial arrangements in overseas investments and a Swiss bank account.

"We put out one already," said Romney, referring the 2010 return. "As soon as the most recent one is complete, we'll put that out."

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Pressed on why he wouldn't release more years, especially after calls by Republican leaders, including Republican Gov. Robert Bentley of Alabama, who over the weekend joined the chorus calling for Romney to release more tax returns, Romney pointed to the legal requirements.

"It's hundreds of pages of documents, and by the way, none of those tax returns are required by law to be put out," said Romney. The law requires him to make public only financial disclosure forms, which Romney has done.

Romney went on to suggest that President Obama should be more transparent himself in light of the "Fast and Furious" scandal.

Romney also used the interview to preview his new line of attack against the president in which Romney accused Obama of "political payoffs."

"There's no question that when billions upon billions of dollars are given by the Obama administration to the businesses of campaign contributors, that's a real problem," said Romney. "I think it stinks to high heaven."