In a small saucepan, bring the water, sugar and mint to a simmer and stir until the sugar has dissolved. Remove from the heat and set aside to cool slightly before removing the basil leaves.
Blend the watermelon until smooth in a blender on the whole juice setting if applicable.
Add the syrup and pulse for a few seconds to mix.
Pour the mixture into your ice pop moulds and freeze for at least 6 hours before enjoying.