In Germany, retailers and the beverage industry have to bear the costs and in return are allowed to keep any unclaimed deposits.

But in other countries the cost is passed on to the consumer.

Several countries with deposit return schemes have a centralised non-profit operating system that runs the collection points and takes back any money from unclaimed deposits.

How much could it cost?

Again, lot of this comes down to how the scheme is designed, so it's too early to put a precise figure on it.

For example, the costs attached to installing a network of "reverse vending machines" will be different to those attached to training existing staff in shops to handle the deposits.

Environmental consultants Eunomia estimated one machine could cost £30,000 to buy, £2,000 to install and another £2,700 a year to operate.

The German system is estimated to have cost about £600m (726m euros) as an initial set-up in 2003, and about £700m (793m euros) annually for maintenance.

A Department for Food, Environment and Rural Affairs (Defra) spokesman told Reality Check: "It's important to recognise that not all deposit return schemes are the same. The specific model, scope and scale of any scheme can have a significant impact on costs and will be part of the consultation."