Orange has apologised to its customers after an unspecified number found themselves without network coverage on Tuesday evening.
The outage was due to a "problem with an area of our network provided by one of our network partners who fixed the issue as a matter of urgency", according to a statement from the mobile operator.
"Like all mobile networks, Orange uses fixed core transmission networks across the UK, in order to route calls effectively. Last night at 5.30pm, part of the core transmission network — that is supplied by our core transmission network partner — broke," the statement continued.
A spokesperson confirmed to ZDNet UK on Wednesday that Orange's unnamed partner had had a "problem with a fibre-optic cable".
Orange's customer services systems also appear to have been affected by the outage, as calls to that service are "routed via this part of the core transmission network".
The outage ended at 7pm. It remains unclear how many customers were affected and in which regions of the UK.