Fast food rivals Starbucks and McDonald's are now on the same team — at least when it comes to developing a cup from sustainable materials.

On Tuesday, McDonald's said it would join with Starbucks and Closed Loop Partners to develop a cup that could be mass produced from materials that are recyclable, compostable or both.

The partnership comes as the food industry finds itself increasingly under pressure to reduce plastic in packaging and single-use items such as straws.

Starbucks and Closed Loop began a collaboration in March to launch the NextGen Cup Consortium and Challenge. The program kicks off in September and invites innovators, entrepreneurs and other experts to submit their plans. To start, NextGen will focus on creating sustainable fiber-based hot and cold cups before seeking solutions for lids and straws.

The brands estimate that 600 billion cups wind up in landfills each year.

McDonald's is committing $5 million to the NextGen partnership, matching Starbucks' pledge. Starbucks also is investing $5 million to join the Closed Loop Fund, which will help fund its infrastructure.

“McDonald’s is committed to using our scale for good to make positive changes that impact our planet and the communities we serve,” Marion Gross, senior vice president and chief supply chain officer at McDonald’s USA, said in a statement.

In the U.S., Seattle has already instituted a ban on plastic straws, utensils and cocktail picks, setting into motion Starbucks' plan to eliminate single-use plastic straws from all of its cafes globally within the next two years. The company already uses plastic lids nationally for some of its drinks, such as Nitro Cold Brew and any beverages topped with cold foam.

The United Kingdom has also announced plans to ban single-use plastic as early as next year, prompting global companies to look for sustainable alternatives. McDonald's said in June that it would begin a phased rollout of paper straws in its U.K. and Ireland restaurants in September.

“A better cup will benefit the entire industry and we invite others to join us as we move these efforts forward," Colleen Chapman, vice president of global social impact at Starbucks, said in a statement.