Newly-released documents reveal that Hillary Clinton's top State Department aide added a major Clinton Foundation donor to a national security board dealing with top-secret information despite the fact that he did not have any apparent experience in the field.

Rajiv Fernando, a wealthy securities trader, gave at least $100,000 to the Clinton's family foundation, and made large donations to her political campaigns.

In 2011, with Mrs Clinton serving as secretary of state, he was appointed to the International Security Advisory Board, a group that advises the State Department on nuclear weapons and other issues of national security.

Members of the board include nuclear scientists, retired generals and senior diplomats. Mr Fernando's area of expertise, in contrast, was high-frequency trading.