WASHINGTON (AFP) - Hillary Clinton's presidential campaign considered tapping Apple chief executive Tim Cook to be her running mate, according to hacked e-mails published on Tuesday (Oct 18) by WikiLeaks.

In an e-mail dated March 17 to Clinton, campaign chairman John Podesta also proposed the mega-billionaire Microsoft co-founder Bill Gates, his wife Melinda and General Motors chief executive Mary Barra as possible Democratic vice-presidents.

"Let me know if there are people you would like to see added or removed," Podesta wrote, enclosing a list of more than 30 names.

"I have organised names in rough food groups."

The e-mail also identified well known military figures - such as Navy Admiral Mike Mullen, former chairman of the Joint Chiefs of Staff, and Marine Corps General John Allen, the former commander of US forces in Afghanistan - as well as Clinton's opponent for the Democratic nomination, Vermont Senator Bernie Sanders and other lawmakers.

Podesta also suggested billionaire former New York City Mayor Michael Bloomberg as well as more conventional political choices, such as Virginia Governor Terry McAuliffe and Ohio Senator Sherrod Brown.

Clinton ultimately settled on Virginia Senator Tim Kaine to campaign with her.

Podesta has not publicly verified that the e-mails are authentic, but told reporters earlier this month that he believed that "Russian intelligence agencies" had hacked into his e-mail account as part of efforts to favour Republican nominee Donald Trump.

US officials have formally blamed state-sponsored Russian hackers for the exposure of internal e-mails from the Democratic party and other prominent people and institutions.