Harry Potter author JK Rowling plans to spread posters of missing Madeleine McCann across the world in the hope of helping to find the four-year-old.

Rowling has arranged, with the assistance of her 65 international publishers, to request for posters of Madeleine to be posted in bookshops worldwide.

The posters will be available from 21 July - the same date as the release of the greatly anticipated final Harry Potter book.

The plan should renew hopes of finding Madeleine who has been missing since 3 May, when she was abducted from her family's holiday apartment in the Algarve resort of Praia da Luz in Portugal.

Information will accompany pictures of the child, offering contact details to the International Centre for Missing and Exploited Children.

Hundreds of thousands of people are expected to see the missing girl's image as they queue to get their hands on Harry Potter and the Deathly Hallows.

Rowling said: "I fervently hope that posters displayed prominently in shops all over the world when the new book comes out will help find Madeleine McCann and will help raise the profile of the many other missing children in different countries."

The parents of Madeleine have expressed their delight at the support. Kate McCann said: "We are overjoyed by this generous offer and would like to thank JK Rowling, her publishers and book retailers for all they are doing to help.

"Madeleine has the first three Harry Potter books and first three DVDs. Like most other children the world over, she loves the stories."