An Post is advising customers not to post any letters to addresses in the Dublin areas of Ballsbridge or Blackrock due to a massive backlog of undelivered post.
The company says a number of staff are refusing to co-operate with new work practices, including refusing to do overtime.
In 2006 An Post and the Communications Workers Union agreed a new nationwide system for collection and delivery of post.
The system has been successfully rolled out in 16 areas across the country.
However, management says staff in Blackrock and Ballsbridge are refusing to co-operate with the new system and as a result a one-week backlog of undelivered items has built up.
A spokesperson for An Post acknowledged that the 2006 agreement had involved substantial change but said the localised problem in Ballsbridge and Blackrock is now so serious, that they are taking out newspaper advertisements tomorrow warning people not to post items to these areas until further notice.
However, there is no problem with posting items from the affected postal zones to other destinations, and counter services in post offices remain unaffected.
The Communications Workers Union acknowledged that there are problems in the two affected postal areas, particularly Blackrock.
National Officer Sean McDonagh said they were working with the company to try to resolve the issues and hope to do so as quickly as possible over the coming days.
