EDINBURGH's festival season has expanded with the opening of the international book festival.

Jeremy Corbyn, Nicola Sturgeon and Chelsea Clinton are among those due to take part in events later in August at this year's Edinburgh International Book Festival (EIBF).

Scotland's First Minister, a regular at the festival, will be in conversation with author Ali Smith in a festival strand named Women Talking and Clinton will discuss inspiring women and children.

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Corbyn is due to be involved in a discussion on "whether the current form of globalised capitalism is forcing democracy towards its ultimate demise" with former Greek finance minister Yanis Varoufakis on August 20.

The book festival adds to thousands of events being held in the Scottish capital throughout August with the international and fringe festivals already under way.

The work of Muriel Spark was marked in her centenary year with Janice Galloway reading a selection of her work at the opening of the EIBF.

Other highlights on the opening day include Philip Pullman, author of His Dark Materials, discussing how he builds his fantasy worlds.

More than 50 writers from around the world have also been commissioned by festival organisers to write essays on freedoms around topics such as race, religion, sexuality and immigration to form the basis of discussions.

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EIBF director Nick Barley said: "The book festival in Edinburgh is an unbeatable place for meeting inspiring people and sharing big ideas.

"This year's programme brings together writers whose experiences will truly change our way of looking at the world: from the emerging Rwandan-Burundian superstar Gael Faye to the legend of Kenyan writing Ngugi wa Thiong'o, this is the most international of festival programmes - but one that also proudly celebrates its Scottish history and context."