An Post has warned consumers that they could be waiting weeks to receive parcels posted before Christmas.
The company has said that limits on international flights mean there is reduced capacity for international letters and parcels on planes.
The company said that many items posted in Ireland during December for delivery outside the country "are still in transit through airports and sea ports".
It said that delivery depots across the globe had been hit by Covid-19, which was also hampering efforts to deliver parcels.
The company expects to be receiving incoming Christmas parcels and letters throughout all of January.
It assured customers that parcels posted from outside Ireland would be delivered as soon as they are received by An Post.
However consumers are complaining not just about international parcels and deliveries.
There are reports of letters being posted from one Dublin address to another Dublin address taking up to a month to be delivered.
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