ROYAL Mail has been hit by a "cyber incident" with customers suffering severe disruption to services.
The mail giant today said its international export services had been greatly affected as a result.
The company said it was currently unable to despatch export items, including letters and parcels, overseas.
It said this would cause "minor delays".
Royal Mail said: "We have asked customers temporarily to stop submitting any export items into the network while we work hard to resolve the issue.
Royal Mail unveil Iron Maiden stamps to pay tribute to heavy metal legends
"Some customers may experience delay or disruption to items already shipped for export.
"Our import operations continue to perform a full service with some minor delays.
"Our teams are working around the clock to resolve this disruption and we will update customers as soon as we have more information.
"We immediately launched an investigation into the incident and we are working with external experts.
"We have reported the incident to our regulators and the relevant security authorities.
"We would like to sincerely apologise to impacted customers for any disruption this incident may be causing."