Only 5% of companies in the FTSE All-Share index are taking steps towards carbon neutrality despite government warnings and pressure from investor groups such as the Carbon Disclosure Project.

A new study from environmental research firm Trucost found 28 out of the 557 companies in the index were managing "carbon risk", up from 15 in 2004, but still only a small fraction of the total. Of those 28, only 11 aim to be entirely carbon neutral.