PRESIDENT Rodrigo R. Duterte on Monday said he would only allow classes once a vaccine for the novel coronavirus has become available.

“I will not allow the opening of classes where the children will cluster together,” he said in a televised speech in mixed English and Filipino.

The presidential palace on Tuesday clarified that the President was only prohibiting face-to-face classes.

“It doesn’t matter if they don’t finish school, for this generation no doctor or engineer will graduate,” Mr. Duterte said in Filipino. “It’s useless to be talking about the opening of classes. For me, vaccine first,” he added.

Mr. Duterte locked down the entire Luzon island in mid-March, suspending work, classes and public transportation to contain the pandemic. People should stay home except to buy food and other basic goods, he said.

He extended the quarantine for the island twice and thrice for the capital region. Metro Manila remains under an altered lockdown until the end of the month, with some businesses allowed to reopen with minimal workforce.

“In the absence of a vaccine and pending the new normal — where there are no more community quarantines — we still won’t have face-to-face classes,” Palace Spokesperson Harry L. Roque said at an online news briefing. “The bottom line is we will not compromise the health of our youths,” he added.

The Philippines has four levels of lockdowns — enhanced, modified enhanced, general and modified general community quarantine.

Under the so-called new normal, restrictions will be eased and minimum health standards should be observed.

Mr. Roque noted that if lockdowns are still in place by Aug. 24 — the scheduled start of the school year — schools should use “blended learning.”

He said schools can use TV, radio and online instructions to teach their students.

Also yesterday, Health Secretary Francisco T. Duque III said it is safe to resume classes in August.

“It’s safe if we open classes by Aug. 24,” he told the Senate health committee. “We just need to ensure that minimum standards of health are in place.”

Mr. Duque was referring to physical distancing measures, frequent hand washing, disinfection of classrooms and other school facilities and provision of alcohol and hand sanitizers.

Schools may also use thermal scanners to monitor students who may be showing symptoms of the coronavirus disease 2019.

Senator Franklin M. Drilon said student safety must be prioritized, while the government measures the capability of students from low-income households to adapt to digital learning.

“I do not see how virtual classes being proposed by the Department of Education can be effectively implemented across all sectors,” he said in a statement. “The poor will be at a disadvantage here.”

He also said that under the law classes must start not later than August.

Meanwhile, the Senate education committee headed by Senator Sherwin T. Gatchalian endorsed a bill allowing Mr. Duterte to set the opening of classes beyond August. — Charmaine A. Tadalan and Gillian M. Cortez