"This means that approximately 80,000 tonnes of oranges might not make it to European supermarket shelves," Justin Chadwick said.

The 2022 rules are for pest control, and require exporters to perform special cooling treatments on their citrus fruits before shipping because of fears over an insect called the false codling moth and a condition called citrus black spot - where unsightly black marks appear on oranges.

Growers are now required to cool their oranges below 2C for 20 days before they are exported.

Mr Chadwick added that the new rules were "unfair and discriminatory" and would require citrus growers to invest $75m (£60m) in new technology and storage, the Reuters news agency reports.

The CGA wants the South African government to raise its concerns at the African Union-European Union Agriculture Ministerial Conference in Rome on Friday.

The body estimates that the new rules could result in a $26m (£20m) blow to the country's orange industry.