In a statement posted to FaceBook and Instagram, brothers Alan and Gary Keery said they would 'be saying Cheerio to their cafés, for now'.
"After a long period of closure due to Coronavirus, and with the future of the hospitality industry looking very uncertain, we have made a decision that our cafés on Brick Lane and Camden will not reopen their doors.
"This is not Cheerio forever, we have goals of seeing our café open again, but due to the current climate it won’t be financially viable for us to run our cafés.
"Fast forward a year or two and we hope to reopen our doors, but until then we will be putting our efforts into growing our online store, creating our own line of products and delivering awesome cereal."
The pair opened their first Cereal Killer Café on Brick Lane in London's Shoreditch back in late 2014.
Dubbed 'the UK’s first cereal café', the business gained cult notoriety for its high price point, which, set against the backdrop of one of the poorest areas of the capital, saw bowls of novelty cereal and milk sold for between £2.50 and £3.50 a helping.
However, its popularity led to the opening of a second London site in Camden a year later; and the pair subsequently expanded to Birmingham in 2016, but that site closed less than two years later.
The group has also opened international locations Dubai, Doha and Kuwait, and it is understood those sites will continue to operate.
"Over the last five and a half years, we have sold over one million bowls of cereal and made a lot of people smile with our 90s themed cafes and cereal themed menu," the Keery brothers added.
"We couldn’t have done any of this without the support of all you amazing cereal fans, so thank you all for letting us live our dreams."