Advertising 
With progress being made in controlling Covid-19 around the world, many countries are considering ways to resume international flights in a safe and sustainable manner. Vietnam is no exception.
On April 1st, 2021, Vietnam Airlines resumed operation of four international routes: Hanoi – Seoul, Hanoi – Tokyo; Hanoi – Sydney; and Ho Chi Minh City – Sydney.
Vietnam Airlines is actively collaborating with authorities to study, develop, and pilot the deployment of “vaccine passports” to ensure safe international commercial flights. We are also the first airline in Vietnam to participate in piloting the IATA Travel Pass application.
Previously, the Civil Aviation Authority of Vietnam reported to the Ministry of Transport about a three-phase plan to re-launch regular passenger flights to Vietnam. In the third phase (starting from September 2021), concentrated quarantine will be waived for passengers bearing: a certificate of a negative Covid-19 test result using the Real-Time PCR technique, issued within three to five days of entering Vietnam; and an internationally approved Covid-19 vaccination certificate.
For now, our international flight network’s gradual recovery only serves Vietnamese citizens wishing to study, work, and visit relatives overseas, and foreigners in Vietnam who meet the entrance requirements and wish to return to their home countries. Inbound flights to Vietnam will serve to repatriate citizens and bring in foreign experts.
While concerns about reopening the sky remain, many countries are working rigorously to devise timely solutions to boost trade and travel while preventing further outbreaks. The British government has established the Global Travel Taskforce to develop an economic roadmap to recovery based on the safe resumption of international tourism. Israel has also announced its decision to welcome vaccinated international tourist groups from May 23rd, with mandatory pre-flight PCR testing and after-flight antibody (serology) testing. The Australian Prime Minister announced that in the second half of 2021, vaccinated Australian citizens can travel abroad if needed and may have to self-quarantine upon returning home.
With various countries adopting these initiatives, airlines are planning to promptly relaunch international flights. Delta Airlines aims to operate flights to Europe, starting with the UK, from Q3/2021. Qantas (Australia) also plans to resume flights to the UK, the US, Singapore, and Japan. 
References:
https://www.travelagentcentral.com/middle-east/israel-to-reopen-to-international-tourism-may-23
