Pakistani authorities announced on Tuesday that most schools would remain closed for another three weeks as thousands of children were infected with COVID-19 amid a third wave of the pandemic.

Students from grades one to eight will remain at home until April 28 before the situation is reviewed again, DPA news agency quoted Education Minister Shafqat Mahmood as saying here.

Classes for grades nine to 12 are to resume on a staggered basis in two weeks, the minister said.

The country reported more than 100 deaths in the past 24 hours on Monday, the highest figure so far during the latest wave of infections.

Fears are rising in Pakistan as more than 10,000 children have caught the deadly virus, health officials said.

The country is heading towards a grim milestone of 15,000 deaths since the outbreak began. Last month, Pakistan closed all schools when the positivity rate of those tested for the coronavirus reached 10 per cent. Levels had slightly improved on Monday when just over 8 per cent of tests were positive. Officials nonetheless called the situation alarming.

The slow rollout of vaccine is also hindering the government's attempts to improve the situation, Pakistan's leading medic Faisal Sultan said.

After supplies were delayed under the global distribution system, Pakistan relied on political ally China for the vaccine. However, only around 1 million people have received their first jab so far, due to the sluggish rollout.

The Pakistan Medical Association, the country's largest body of health care professionals, has advised the government against reopening schools until the current wave of cases subsides.