World Cup fever in Argentina, home of the defending champions, has boosted sales of counterfeit jerseys and soccer trading cards, sparking protests from retailers who are already under pressure from President Javier Milei's market-opening policies.

The main shopping streets of Buenos Aires are flooded with hats, flags, mate gourds and t-shirts in patriotic light-blue and white colors.

Argentina's World Cup victory in 2022 "makes people who don't even like soccer feel that passion," said Fabián Castillo, head of the Buenos Aires commerce chamber.

But he suspects more than 70 per cent of the Argentine national team jerseys sold on the street are counterfeit. Around the world, many consumers say they knowingly buy low-priced imitations because of the often high prices of official jerseys.

That is particularly the case in Argentina, where residents' purchasing power has dropped as salaries have failed to keep up with inflation. The sales of counterfeit goods add to other challenges facing the local textile industry, which has seen factories close due to an increase of cheap imports under Milei.

Lucas Aranda, a textile merchant from the province of Buenos Aires, sells national team jerseys for 40,000 pesos ($28) each, about a quarter the cost of originals.

Counterfeits have also spread to the popular soccer stickers that children - and many adults - collect to complete their World Cup albums. While originals can be found at convenience stores, cheaper "alternatives" are offered online.

The World Cup kicks off next month, hosted by the United States, Canada and Mexico. Argentina's first match is against Algeria on June 16.