A top aide to Bill Clinton warned fellow Clinton Foundation advisers against making "too many rules" regarding conflicts of interest at the charity due to the former president's overlapping personal, political and philanthropic pursuits.

Justin Cooper, a longtime staffer who managed Hillary Clinton's private server at the State Department, told other high-level aides in Nov. 2011 that he shared the concerns of Doug Band, another longtime staffer, over the possibility that Bill Clinton might soon be asked to sign a disclosure form.

"I think there [sic] WJC may have some real serious conflicts if we start to make too many rules," Cooper wrote, using Bill Clinton's initials, in an email made public Friday by WikiLeaks. "It may be time to update some procedures but we can not ignore the nexus of WJC's life."

Cooper's warning came at a time when the Clinton Foundation was undergoing a corporate review given the conflicts and bureaucratic excess that had begun to plague its operations.

Chelsea Clinton earlier sounded the alarm about rumors that Band had invoked her father's name, without his knowledge or consent, in order to woo British clients for his newly-founded consulting firm, Teneo Strategies.

Band reacted strongly, called Chelsea Clinton a "spoiled brat kid" and followed up with a memo that laid out Teneo's involvement in bringing personal profits to Bill Clinton and big donations to his foundation.

That memo, in which he described the nexus of the former president's multi-million dollar enterprises as "Bill Clinton Inc," included examples of lucrative speaking deals Cooper and Band secured for him. In some of those examples, the speaking deals involved a parallel donation to the Clinton Foundation, further blurring the lines between Bill Clinton's personal profits and eponymous charity.

Cooper appeared before Congress in September and testified that he had constant access to Hillary Clinton's private email server during her State Department tenure.

The longtime Clinton aide also netted a six-figure salary from the foundation during that time, according to emails published last month by WikiLeaks.

The transparency website has, since Oct. 7, published more than 47,000 emails taken from the inbox of John Podesta, Hillary Clinton's campaign chair. The Democratic nominee's team has declined to comment on the emails' contents, citing the purportedly illegal nature of how WikiLeaks obtained the messages.

But Clinton has faced more than a year's worth of questions about the intersection of her State Department work and her family's foundation, as well as whether her husband's financial relationships may have affected her diplomatic decisions.

The FBI has reportedly opened a sprawling investigation into the Clinton Foundation amid allegations of quid pro quo and financial misdeeds.