Some of the biggest names in grocery have still not signed up to the Courtauld Commitment to reduce packaging waste.

This week, the Waste & Resources Action Programme revealed the names of 12 new grocery players that have lent their support to phase two of the voluntary responsibility deal and, while this takes the total number of signatories to 48, there are some big gaps in the list.

Discounters such as Aldi and Lidl are missing, as are suppliers Kellogg's and PepsiCo, which admitted in its most recent sustainability report that it still had some way to go to meet its packaging targets.

"We have signed up a lot more of the big names, but there are a few more we would like to see on board," said a Wrap spokeswoman, who hoped the new names would encourage others. "When one big retailer or manufacturer signs up, the others tend to follow suit as they want to be seen to be doing as well as their competitors."

The six biggest grocery retailers are already on board and the 12 new signatories include Associated British Foods, Coca-Cola Enterprises, Cafédirect, Kraft Foods, Premier Foods and P&G.

"For us it made sense to sign up," said Wolfgang Weinmann, Cafédirect head of strategic development. "Not only does it complement our values as a business but it is a great opportunity to collaborate with like-minded companies."

Under phase two, companies have pledged to cut the carbon impact of packaging by 10%, household food and drink waste by 4% and product and packaging waste in the supply chain by 5%.