A fleet of 150 electric buses manufactured by Chinese company BYD is moving from the San Antonio Port to the Chilean capital Santiago, on June 6, 2020. (Xinhua/ENELl)

Up to 2,000 trucks are backed up at Argentina's main border crossing with Chile due to tougher COVID-19 testing requirements, Argentine haulers said on Tuesday, adding that the supply chain could suffer due to the delay.

Usually within a day, some 900 trucks will pass through the Christ Redeemer crossing from the Argentine province of Mendoza into Chile.

However, the trucks have been backed up for two days, after tougher health controls being imposed on Argentine haulers by Chile, the Argentine Federation of Freight Business Entities indicated in a statement.

"At any moment the supply chain is going to break. It's not a funnel, it's a plug. Effectively, the border is closed," Daniel Gallart, from the Mendoza truck owners association, told AFP.

"We're talking about 1,800 or 2,000 trucks," Gallart added.

Truck owners are now demanding the Argentine Foreign Office intervene.

Meanwhile they also want more testing posts to speed up the process.

The delays are costing millions of dollars for the international trade that passes through Chile towards ports on its Pacific coast. 

The trucking industry has already been hard hit by the pandemic.

Both countries have high levels of vaccinated people.

Argentina is in the middle of new wave of infections from the highly contagious Omicron variant.

The country has seen around 120,000 new COVID-19 cases and a total of 200 deaths a day.

AFP