It may be the beginning of the end for plastic bottles, as two major supermarkets prepare to trial an eco-pouch for milk.

Tomlinson's Dairy near Wrexham already supplies milk in the new environmentally friendly packs to local schools and shops but hopes they could be in multiples later this spring.

It is the first UK dairy to pack milk in this way, although both Tomlinson's and Dairy Crest considered the technology back in 2003.

"We weren't convinced then that customers were ready for a greener choice of milk packaging," said Philip Tomlinson, MD of the dairy. "Four years on, the focus is very much on the benefits of environmentally friendly packaging. Our trials have proved that demand for milk pouches is now very strong."

Dairy Crest said it was watching the trials. "We would consider investing in the technology if there were strong demand for it," said milk purchasing director Arthur Reeves.

Pouches come in a third of a pint and one-litre sizes and have proved a big hit during trials at a local primary school and on doorstep delivery routes. They will also be available soon in local independent stores. Schoolkids receive pouches with straws, while those delivered to homes and shops are provided with a jug that pouches go into.

The pouches cost less to produce and distribute than normal polybottles, with around 160 one-litre pouches taking up the same space as a one-litre volume plastic bottle, saving significant transport costs. When they go on to landfill, the pouches take up 90% less space than standard bottles and are biodegradable within a year.

This last attribute could prove a big winner with the public, said Neil Blackburn, from Kite Consulting, who has been working on the project. "The likelihood of a rubbish tax being introduced in the future will certainly fuel demand."