The children’s show Blue Peter shall fly the two winning children to China to perform an important and unique role at the heart of the handover ceremonies.

These two opportunities are incorporated into both closing ceremonies of the Beijing Games and officially mark the beginning of the journey to the London 2012 Games. These spectacular shows are expected to be watched by a worldwide audience in excess of 2 billion viewers.

To enter the competition, children will need to write a postcard to an imaginary child in Beijing, telling them why they are excited about either the Olympic or Paralympic Games. They will describe something that they love doing and include a photo that shows them doing it.

Entry to the competition is via post or the Blue Peter website. Entries must be received by midnight on 31 March 2008. The Postcard To Beijing competition is open to all 6 to 12-year-olds, who are UK citizens.

The details will be announced on-air and will be available on the Blue Peter website, bbc.co.uk/bluepeter, alongside all related terms and conditions of entry.