SEOUL (REUTERS) - South Korea closed its first phase of reservations for Johnson and Johnson Covid-19 vaccines on Tuesday (June 1) as military personnel signed up for all 800,000 shots on offer, the government said.

South Korea received one million doses of the vaccine this week after the United States almost doubled a pledge made during President Moon Jae-in's first summit with US President Joe Biden last month.

The authorities have designated the vaccine for military-related personnel, including reserve forces and the civil defence corps, as well as people planning overseas business trips or diplomatic missions.

Around 3.7 million people are eligible to receive the single-dose vaccine and a total of 800,000 have signed up in less than 16 hours since reservations began on Tuesday, the Korea Disease Control and Prevention Agency (KDCA) said in a statement.

The KDCA closed the reservations at 800,000 doses, but said others can book their shots when more vaccines are available.

South Korea has inoculated 5.79 million people, or 11 per cent of its population, with the first dose of two-dose vaccines from AstraZeneca or Pfizer. It aims to vaccinate 14 million by the end of this month.

It said the plan is on track as more vaccine shipments are due to arrive later this month and willingness to get vaccinated appears to be rising, lured by incentives.

A survey in May showed 69.2 per cent of respondents were willing to get vaccinated, up from 61.4 per cent a month earlier, senior health official Lee Sang-won told a briefing.

The government on Tuesday allowed people who have received at least one dose to have family gatherings without restrictions and visit nursing homes.

Those fully vaccinated will no longer be required to wear masks outdoors from July.

The country reported 459 new confirmed cases on Monday, bringing the total tally to 140,799 infections, with 1,963 deaths.