WASHINGTON (AP) -- President Barack Obama and first lady Michelle Obama held assets last year that were worth between $1.8 million and nearly $7 million, according to federal financial disclosure forms the White House released Wednesday.

Required by law, the forms allow public officials to list their assets in broad ranges, such as between $1 million and $5 million, which makes it difficult to determine a precise net worth.

Obama signed the eight-page report Tuesday and the White House released it Wednesday as the president remained on the defensive over how the administration explained last September's attack on a diplomatic mission in Benghazi, Libya, that killed four Americans, including the U.S. ambassador.

Obama also has been buffeted in recent days by the disclosure that the Internal Revenue Service targeted conservative groups and the Justice Department's decision to secretly obtain two months of records for multiple telephone lines used by Associated Press reporters and editors.

The disclosure forms show the largest jointly owned asset was Treasury notes worth $1 million-$5 million. The Obamas also had $250,001-$500,000 in a JPMorgan Chase checking account, and $100,001-$250,000 in Treasury bills.

The president and first lady also each had $100,001-$250,000 in individual Vanguard retirement funds.

The only liability listed was $500,001-$1 million on a 30-year mortgage on their Chicago home, at an interest rate of 5.625 percent.

The president also collected a total of between $250,000 and $2.1 million in royalties on his three best-selling books, "Dreams From My Father" and "The Audacity of Hope," plus a children's book, "Of Thee I Sing: A Letter to My Daughters."

Vice President Joe Biden reported holding assets last year worth between $120,000 and $550,000, mostly in investment accounts and life insurance policies. Among them were a United States Senate Federal Credit Union savings account held jointly with his wife, Jill, valued at $1,001-$15,000.

Biden represented Delaware in the Senate for 36 years before he was elected vice president.

Biden also listed as an asset a Wilmington, Del., rental property owned with his wife valued at $100,001-$250,000.

Biden's liabilities included the mortgage of $500,001-$1 million, and several home equity lines of credit.

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Online:

Obama, Biden financial disclosure forms: http://1.usa.gov/10z1pdF

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