The fast-food company announced last year plans to switch to paper straws in the United Kingdom and Ireland in 2019 as part of McDonald’s “goal to source 100% of guest packaging from renewable, recycled, or certified sources by 2025 and to have guest packaging recycling in all restaurants globally.”

However, the recent paper straws, McDonald’s told Fox News, are not able to be recycled because of problems with waste processing.

“We have moved quickly to paper straws — balancing the more positive impact they have on the environment with finding a straw which meets customer expectations,” a spokesperson said. “Whilst the materials the straws are made from are recyclable they cannot currently be processed by waste solution providers and local authorities unless collected separately.”

The problem “is a wider industry issue, as the infrastructure needed to recycle has not kept pace with the emergence of paper straws,” the spokesperson added.

“We are working with our waste management providers to find a sustainable solution, as we did with paper cups, and so the advice to put paper straws in general waste is therefore temporary,” the company said. “This waste from our restaurants does not go to landfill but is used to generate energy.”

The previous plastic straws McDonald’s provided were also recyclable, but faced the same issue, according to the representative.

Many cities and countries have looked into or plan to ban plastic straw usage in hopes of addressing the world’s plastic pollution problem. Scientists said in spring 2018 that nearly 7.5 million plastic straws were lying around America’s shorelines — and figured that 437 million to 8.3 billion plastic straws were lying on the entire world’s coastlines.

Paul Pomroy, CEO of McDonald’s in the U.K., said last year that “together with our customers we can do our bit for the environment and use fewer straws.”

The debate surrounding plastic usage, particularly straws, became heated in 2015 after a video shows rescuers removing a straw from a sea turtle’s nose in graphic and bloody detail.