McDonald's has admitted that the paper straws in its United Kingdom and Ireland branches can't be recycled.
The paper straws were introduced last year as an environmental policy to replace recyclable plastic ones.
All Hong Kong McDonald's outlets - around 230 of them - launched a "No Straw Everyday" campaign in December last year, where staff members do not offer plastic straws to customers unless requested.
Driven by the motive to make "wider efforts to protect the environment," McDonald's replaced plastic straws with paper alternatives across all its 1,361 stores in the United Kingdom and Ireland last year.
However, the fast food chain earlier this week admitted its paper straws are "too thick to be processed" by its recyclers - unlike the recyclable plastic ones.
The food giant's response came after a British publication, The Sun, issued a memo to its staff and reminded them to dispose of paper straws from McDonald's in general waste.
However, the paper straws have been unpopular as numerous netizens complained they become wet and soggy in drinks.
Some petitioned - with over 50,000 signatures so far - asking for McDonald's to bring back the plastic straws.
Responding to The Standard's inquiry, a McDonald's Hong Kong spokesman said the fast food powerhouse launched a no straw campaign to encourage customers to use less plastic straws.
However, the spokesman did not comment on the paper straws or whether Hong Kong branches will introduce paper alternatives.