After years of teasing plans to eliminate plastic foam cups from all of its stores, Dunkin Donuts says its finally ready to deliver.

The popular coffee chain announced on Wednesday that it would replace all its polystyrene foam cups with sustainably sourced, double-walled paper cups by 2020. That milestone achievement, which the company said would eliminate nearly 1 billion foam cups from the waste stream annually, follows Dunkin announcing a similar goal for 2016.

Though the company missed that mark, its not because they havent been trying, a Dunkin spokesperson said.

In an email to HuffPost on Thursday, the company said replacing the foam cups has been a No. 1 priority issue, but suggested that an unpopular lid is to blame for the delay.