Visitors to the Scottish government buildings will now be required to bring in their own reusable mugs if they wish to partake in a hot beverage away from a cafe location.

The new rule, which bans single-use coffee cups in many main buildings, will take effect on June 4 in an effort to reduce the astronomical amount of disposable cups used each year in the buildings. Officials estimate that over 450,000 cups are thrown away each year in government offices.

Affected locations include all of the cafes and restaurants in Saughton House, Victoria Quay, Marine Lab, St. Andrew’s House, Atlantic Quay, and Buchanan House. Visitors can still order warm beverages to be consumed onsite in ceramic mugs. Building staff are encouraged to bring in their own reusable containers for personal use. Workers in the buildings were told of the changes at the beginning of May to allow for ample preparation.

The new rule follows the lead of the Scottish Parliament, which banned the use of plastic drinking straws in its bars and cafes. By making this move, the Parliament building was able to eliminate the use of approximately 4,00 plastic straws every year.

The ban on single-use cups was encouraged by Environment Secretary Roseanna Cunningham. She asserts that Scotland is eager to lead by example and also followed the lead set by the European Union (EU). Last week, the EU proposed a ban on many disposable plastic items including plates, cutlery, and straws. The proposal by the European Commission is an effort to minimize the growing and concerning issue of ocean pollution.