Hillary Clinton has begun on a promotional tour for a book in which she defends her time as the US secretary of state.

Analysts say the book's content, and the tour, is an attempt to lay the groundwork for a second run at the presidency.

Clinton says she differed with the US president, Barack Obama, on policies including Egypt and Syria.

Al Jazeera's Tom Ackerman reports from Washington.

Source: Al Jazeera