Clinton quizzed her aides after she was sent a news story during Obama's reelection campaign about husband Bill going off-message

An exasperated Hillary Clinton quizzed aides on how to keep her husband in check during the 2012 election, in new emails released by the State Department.

In one message, State Department counselor Cheryl Mills sent Clinton a Washington Post article during Obama's 2012 reelection bid entitled 'Bill Clinton's ego could cost Obama in November'.

In the story, analysts questioned whether Bill's inability to stay on message could harm Obama's campaign. A short while later Clinton responded 'What can be done?', the New York Post reports.

The message was revealed in a trove of more than 550 that were released on Saturday, three of which were deemed to be 'secret', while another 84 were labelled classified.

One of the messages is a long note from David Satterfield, a top US diplomat to Egypt, who told White House and State Department officials about negotiations in the Sinai.

The message's contents have been deemed 'secret', though there is no sign they were labeled such at the time in which the email was sent, according to the Washington Times.

Clinton was forwarded the message by top aide Jacob Sullivan who asked Clinton to calm down the 'hysterical' US Ambassador to Pakistan, Cameron Munter, following the assassination of Osama bin Laden at a compound in Abottabad.

'Can you get me the facts (such as they are) before I talk with Kerry?' Clinton replied. The remainder of the email is highly redacted.

The department has now released more than 45,000 pages of emails from the private account Clinton used as secretary of state.

It plans to finish making her emails public on February 29, a day before the critical Super Tuesday primaries.

The news story questioned whether Bill could keep his ego in check for long enough to deliver Obama's message without going off on his own tangent. A despairing Hillary asked: 'What can be done?'

But ahead of the deadline previous deadline - January 29 - the State Department told the judge that they had discovered 4,000 additional emails that had not been checked for classified or private material.

The a top State Department open-records official took blame for not hitting the January deadline.

Clinton has struggled to put the email controversy to rest as she seeks the Democratic presidential nomination.