Its Ministry of Foreign Affairs announced on Tuesday the new rules would be applicable only to those who have a valid residency permit and left the kingdom on exit and reentry visas after receiving two doses of Covid vaccine from Saudi Arabia, Saudi Gazette newspaper reported.
Visitors from Vietnam and 12 other countries are currently barred from direct travel to Saudi Arabia under the kingdom's travel restrictions.
So far, only AstraZeneca, Pfizer, Moderna, and Johnson and Johnson have been approved by the Saudi health authorities. All arrivals in the country will be required to provide proof of vaccination along with a negative PCR test.
Saudi Arabia had earlier announced a three-year travel ban for citizens who visit red-listed countries and slapped a 500,000-riyal ($133,300) fine on travelers coming from these countries as part of tougher measures to keep out the Delta variant.
Saudi Arabia has reported over 542,000 Covid cases and nearly 8,500 deaths so far.
Vietnam is currently facing its most challenging Covid outbreak, triggered by the Delta variant, which has prompted several countries to ban or impose stricter quarantine measures for travelers from the country.
In the ongoing wave that began in late April, the country has recorded over 365,000 cases.