The South African Post Office (Sapo) has appealed to customers sending airmail abroad to ensure that items in the mail are permitted into the destination country.

This comes after the airmail service between South Africa and China has resumed with immediate effect after the reopening of the Chinese borders.

The Post Office said it has seen large volumes of mail sent to New Zealand since the reintroduction of airmail to the country.

In a statement on Wednesday, Sapo advised customers to use information provided by the website of the postal administration in the destination country to check for items that are allowed.

"The parcel should be sturdy, the address correct and the receiver's mobile phone number should appear on the parcel. The post office in the destination country needs it to send the receiver a text message to collect the item," the post office said.

New Zealand and Australia, for example, do not allow in any items made of wood or straw. This means that a traditional pencil, for example, will be confiscated.

Airmail to Germany and Brazil remains suspended owing to a lack of cargo space on aeroplanes.