The government on Sunday approved the closure of Ben-Gurion International Airport, Israel's main port of entry, from Tuesday until the end of the current lockdown aimed at halting the spread of the coronavirus.
The move, Prime Minister Benjamin Netanyahu said, would "hermetically seal" the state.
The plan approved by the government includes the full closure of the airport until the lockdown ends next Sunday, with the exception of flights for humanitarian purposes and extraordinary circumstances.
It comes in response to the emergence of several new strains of the virus, which are more infectious and potentially more harmful.
"Just in this week of closed skies alone, another million Israelis will be vaccinated," Netanyahu, who had been pushing for the closure, told his government at the start of the meeting on the issue.
"Given the increase in variants, which is leading to a record infection rate and possibly more deaths, I said let's close down first of all," he said.
"Contrary to public discourse, we closed the skies in the normal format from April to August. Now we are literally closing, with no commercial flights and nothing save for exceptional circumstances. First of all, we close."
The prime minister had originally been seeking to close the airport for two weeks, following consultations with Health Ministry officials and the National Security Council late Saturday over the spread of mutated coronavirus strains.
"I realized the issue of the urgency due to the mutations [of the virus] in the world. Not only are the variants out there... it's enough that one comes in and we did not catch it," he said earlier Sunday.
Israel in the midst of a massive push to vaccinate the entire adult population as swiftly as possible. So far, some 25% of the total population has received at least the first dose of the two-stage vaccine and close to 10% had already received the second jab.
Health Ministry officials warned the variants cause more severe illness, which is not always detected by existing testing methods after six pregnant women hospitalized in serious condition with COVID-19 were found to be infected by the new mutation of the virus first seen in Britain.
"Our central viral laboratory has thus far received 10 samples from pregnant women suffering from COVID-19. We have completed the DNA sequencing of seven of those samples and found six of them to be of the British variant," a ministry official said.
The ministry is urging pregnant women to get vaccinated for coronavirus as soon as possible.
The Military Intelligence coronavirus taskforce working with the Health Ministry to combat the spread of the virus has warned that a local variant may also appear.