Former US Secretary of State Colin Powell has criticised both candidates in the presidential election in hacked emails leaked by a group intelligence officials suspect is linked to Russia.

Hillary Clinton, he says, is “greedy” and has “unbridled ambition”, adding that he’d rather not have to vote for her.

But her Republican rival comes in for a stinging attack. Powell calls Donald Trump a “national disgrace” and an “international pariah”. He also derides the tycoon’s attempt to attract African-American voters.

The former Secretary of State served under George Bush and played a key role leading to the invasion of Iraq.

The White House has so far refrained from publicly blaming the hacking behind the leaked emails on Russia.