Israel is to offer a third booster dose of the Pfizer vaccine to over-60s in a bid to keep the delta variant at bay, becoming the third country to run a live trial of a three-jab vaccination plan.
Israeli officials took the decision after seeing evidence that the first people to be vaccinated against Covid in January were now more susceptible of catching the virus due to fading antibody levels.
Israel follows Hungary and Turkey, which have already announced that they will begin offering a third dose of Covid vaccines to the elderly.
Nachman Ash, the director general of the Israeli health ministry, told healthcare providers to begin offering third doses from the start of next week, according to local media reports.
At the start of 2021, Israel's Covid vaccination programme became the fastest in the world, with the majority of the adult population given two doses within a matter of weeks.
One study by Hebrew University published earlier this week found that the vaccine efficacy rate in preventing infections had fallen from more than 90 per cent to just 80 per cent.
However, Israeli officials stressed that the vaccines remained overwhelmingly effective in preventing death and serious illness.
Israel is currently in the grip of a new wave of coronavirus which has seen the infection rate rise to more than 2,000 cases per day.
Naftali Bennett, the prime minister, has subsequently revived the Green Pass, a vaccine passport which permits entry to large indoor gatherings to those who have been vaccinated.
"Our strategy is clear - to safeguard life, and to safeguard daily routines in the State of Israel,” said Mr Bennett.