Soak the jelly in cold water. Make balls with the
watermelon pulp. Peel the
orange and separate the segments. Heat 1/2 l of water in a pan, add the sugar and boil for 10 minutes. Take the pan off the heat and add the drained jelly, melt stirring continuously. Leave to cool, add the champagne and mix. Put the
watermelon balls into the bottom of a crown mould and carefully add the champagne jelly. Leave in the fridge for 30 minutes and when the jelly begins to set, decorate the walls of the mould with
orange segments. Leave the mould in the fridge for another 3 hours. When serving, put the mould under hot water and turn it out quickly onto a tray to de-mould.