SEOUL (NYTIMES) - South Korea plans to ship almost 1.6 million doses of AstraZeneca's Covid-19 vaccine to Vietnam and Thailand this week, its Foreign Ministry announced on Tuesday (Oct 12), as the South-east Asian nations struggle to contain the spread of the virus.

The donation comes as South Korea's vaccination programme has accelerated rapidly, with 70 per cent of the population expected to be inoculated by the end of the month.

About 62 per cent of South Korea's total population has been fully vaccinated, according to the Ministry of Health and Welfare, and the nation is expected to ease the most severe restrictions by next month.

Thailand has fully vaccinated 33 per cent of its population and Vietnam about 17 per cent.

About 1.1 million doses will go to Vietnam and 470,000 to Thailand, South Korea's government said.

South Korea was among the last of the world's wealthiest nations to start a vaccination programme, leading to frustration among citizens who had already spent a year living under restrictions to control the spread of the coronavirus.

Eight months later, the country has inoculated more people per capita than the United States, which has secured the largest supply of vaccines in the world.

The US government invested about US$1.2 billion (S$1.62 billion) in the development of AstraZeneca's vaccine, hoping that it would be one of many in an arsenal.

Instead, federal officials have yet to approve the use of the shot and millions of doses are sitting unused, likely destined to be exported.

US President Joe Biden has promised to donate up to 60 million doses of the AstraZeneca vaccine to countries in Latin America, South-east Asia and Africa.

AstraZeneca's vaccine is cheaper and easier to store than the mRNA vaccines produced by Pfizer and Moderna, but it has been dogged by production mishaps, questions about its efficacy and reports of rare blood clots.

Amid the concerns, South Korea temporarily suspended use of the vaccine in April but cleared it for use again several days later.