BUENOS AIRES — Argentina’s government opened some of its border to tourists from Chile and Brazil on Monday for a four-day test run as cases of COVID-19 have declined.

The measure applies to two crossings into the provinces of Mendoza, a wine-producing region that neighbors Chile, and Misiones, which borders Brazil hand has the famed Iguazu Falls.

Prior to the pandemic, thousands of people crossed daily over those borders.

Visitors will still need to show they have completed a full vaccine course at least 14 days before arriving, show a recent negative PCR test and accept a fast antigen test on arriving.

They won’t have to quarantine, but will required to have another PCR test if they stay beyond seven days — and those who test positive would then have to quarantine.

The announcement amounts to an early start on a gradual opening of land borders that already had been announced for citizens of neighboring countries that was to start on Friday. Fully vaccinated Argentines living abroad will no longer have to quarantine on arrival.

The country of about 45 million people has seen steadily improving levels of infection and hospital bed occupation after being hit hard by the virus. Overall, it has recorded 5.2 infections and more than 114,000 deaths.