Concerns over tea shortages are brewing in the U.K. But how serious is the threat to supply? [Video]

Written in black and white, a small sign in one of the United Kingdom’s biggest supermarket chains warned customers of a possible shortage of tea.

“We are experiencing supply issues affecting the nationwide supply of black tea,” the sign, posted mid-February in Sainsbury’s, read. “We apologize for any inconvenience and hope to be back in full supply soon.”

In November, Yemen’s Houthi rebels began launching attacks on vessels in the Red Sea in solidarity with Palestinians in the ongoing Israel-Hamas war.

Since then, shipping companies have been forced to stall or redirect to different trade routes, causing weeks of delays. That’s caused concern on social media for Britain’s legion of tea drinkers, worried that the unrest will disrupt the shipments tea retailers rely on.