E-Passport gates have been down at UK airports.
The issue is likely to cause long delays for bank holiday travelers as all airports in the country that use the gates are affected.
The Home Office confirmed the news, but did not say how long the failure would last.
A Home Office spokesman said: “We are aware of a nationwide border system issue affecting arrivals to the UK.
“We are working to resolve the issue as soon as possible and are in contact with port operators and airlines to minimize disruption to travelers.”