Candace Bushnell will join a host of writers at the event

The writer, famed for her Sex and the City tales of single women in New York, will join US literary giant John Irving and Booker-prize winner Ben Okri at this year's event.

The festival, which is held in Edinburgh's Charlotte Square Gardens, will see more than 550 authors attending with highlights including a look back at the work of George Orwell, who would have been 100 this year.

Trainspotting author Irvine Welsh, crime writer Ian Rankin, playwright Alan Ayckbourn and veteran BBC war correspondent Kate Adie will also spearhead a strong homegrown line-up at the event, now in its 20th year.

Journalist and broadcaster Clive James, anti-war campaigner Tariq Ali, historian David Starkey and fertility expert Lord Robert Winston have been lined up to give talks.

Also planned are a series of topical discussions on the effects of war and debates on the relationship between Christianity and Islam.

Former BBC war corrospondent Kate Aidie will also attend

Festival director Catherine Lockerbie said the appeal of the book festival is increasing each year with the public hungry to talk about books on a much more diverse range of subjects.

She explained: "We've seen over the last few years an incredible growth in demand for what the Edinburgh International Book Festival offers: excitement, discovery and the chance for a really good argument.

"The public are hungry to talk about books and subjects of every kind, to swap ideas with the world's leading thinkers, to feel their heads buzzing with new thoughts.

"For 2003, we've aimed to create a programme with some of the greatest names in world writing, which will whet and feed that appetite even further."