Internet rumours and a mysterious poster on the London Underground have started theories about new Coldplay material coming soon, Gigwise reports.

A poster pinned up on the London underground shows a series of rainbow colour spirals diagraming the Flower of Life will be the artwork for the new Coldplay album title A Head Full Of Dreams due for a 4 December release.

There isn't any official report yet but the colour scheme and typeface matches the band's website formatting performing and the logo on the poster matches the same logo that was seen on a T-Shirt Chris Martin was wearing recently.