"Following a joint investigation with our air freight partners and New Zealand Post, a backlog of approximately 12,000 items was discovered at Auckland Airport and these have now been processed by NZ Post who have advised deliveries will be arriving into homes over the next few days and everything will be delivered by Saturday 22nd December.
"We sincerely hope you can accept our apologies for the frustrations this delay has caused."
But a spokesperson for New Zealand Post, Michael Tull, said the delays did not occur in New Zealand, rather prior to the deliveries arriving in the country.
"There was no backlog of packages found at Auckland Airport ... [The Book Depository has] chosen their words poorly. A backlog from overseas arrived at Auckland Airport yesterday and is being processed by New Zealand Post and will now be on its way out to people," Mr Tull said.
"But it's just an unfortunate choice of words because it sounds like a backlog or a big pile of books sitting at Auckland Airport - that is not the case."
Mr Tull said the deliveries which arrived in New Zealand "absolutely should" be delivered to customers prior to Christmas.
"But I can't speak as to whether there are any other consignments, whether [yesterday's arrival] was all of it or whether there are other Book Depository products which have not yet arrived."
Mr Tull said he was not in a position to comment on who was responsible for the delay.
Book Depository later sent the following tweet: "Further to our earlier message we would like to clarify the delays are not as a result of backlogs or delays @nzpost New Zealand Post ..."
"... rather as a result of capacity issues prior to arrival in New Zealand. We're pleased the books are on the ground and on their way!"
He said New Zealand Post mail centres were well staffed to deal with the increased volumes of deliveries ahead of Christmas.
- nzherald.co.nz