Indoor chicken production is one of the most sustainable forms of meat production, according to British Poultry Council chairman Ted Wright.

And the sector has just become even greener, smashing targets on energy savings. Participants in the climate change agreement with Defra had cut their energy use 28% in the first four years alone, against a 14% reduction target over 10 years.

The targets have now been renegotiated with Defra to specify a 30% cut.

"Our sector is already the most environmentally sustainable of all livestock sectors," Wright said.