NEW YORK - The Obama re-election campaign tonight is seizing on a report that suggests Mitt Romney is using ethics exceptions to avoid disclosing some of his financial investments. Obama's team has gone as far as using the president's Twitter handle to lob attacks on the GOP candidate.

The account linked to the president's name tweeted a link to the report, published by the Washington Post, that said that Romney has "taken advantage of an obscure exception in federal ethics laws to avoid disclosing the nature and extent of his holdings."

"By offering a limited description of his assets, Romney has made it difficult to know precisely where his money is invested, whether it is offshore or in controversial companies," the article said.

In addition, the Post reported that in 48 accounts from Bain Capital, the firm Romney founded in Boston and touts daily on the trail, he did not reveal his assets.

While the Romney campaign maintains that the candidate followed the law, the Obama campaign released a statement accusing Romney of "exploiting a loophole in order to shield his assets and investments from public review."

"Mitt Romney has put his personal financial assets in a black box and hid the key, attempting to play by a different set of rules than any candidate in recent history," said Obama's campaign manager, Jim Messina.

"Gov. Romney provided 23 years worth of tax returns to the McCain campaign so they could determine if he would make a suitable vice president," wrote Messina. "He must meet that same standard now so that the American people may judge whether he would be a suitable president, and whether there are any conflicts of interest that could cloud his judgment."

The release from the Obama campaign also recommended a Twitter hashtag to highlight the report, "WhatsRomneyHiding," that has since been used by several members of the Democratic National Committee.

In a written statement to ABC News, Romney campaign spokeswoman Andrea Saul said, "President Obama will do anything to try and distract Americans from his failed record of chronic unemployment, lower incomes and higher gas prices."

"The PFD completely and accurately describes Gov. Romney's assets as required by the law applicable to candidates for president," said Saul. "If [the U.S. Office of Government Ethics] had at any point considered any part of the filing insufficient, it would have made this clear."