Afghanistan is running out of hospital beds as suspected cases of coronavirus surge, officials said on Saturday, warning "there is a disaster coming" in the impoverished country.

Afghan health authorities reported 761 new positive cases of COVID-19 over the past 24 hours, taking the total number of confirmed infections to 19,551.  "Our (hospital) beds are almost full, we won't have any more capacity very soon," Health Minister Ahmad Jawad Osmani told reporters.

Officials said the number of cases were more than expected, including in the capital Kabul, the epicentre of the disease. "There is a disaster coming," said Kabul governor Mohammad Yakub Haidary at a joint press conference with the health minister.

He said in Kabul alone there could be a million people infected with the deadly virus. So far there have been 327 confirmed deaths in the country. "We have reports of increasing suspected deaths, people burying dead bodies at night," Haidary said. "We fill 10-15 ambulances of dead people every day."

The virus's spread has surged amid a nationwide lockdown that residents have largely ignored, with many daily wage earners taking their chances with the disease rather than lose a day's work. But the minister said that from Sunday the authorities will strictly impose measures like wearing face masks and maintaining social distancing for the next three months in order to curb the spread of the virus.

Experts say that Afghanistan is able to test only about 20 percent of its daily suspected coronavirus cases. The International Rescue Committee (IRC) said in a statement Tuesday that "between 80 to 90 percent of potential cases are not being tested", citing figures provided to them by the health ministry which said between 10,000 and 20,000 samples were being received per day.

The charity warned that Afghanistan was on the brink of a health crisis after confirmed cases spiked by 684 percent in May. Afghanistan has one of the highest rates of tests coming back positive -- about 40 percent -- the IRC said, indicating high levels of undetected infections.

The spike in cases came after Afghanistan grappled with rising violence in recent months that diverted vital attention and resources away from the fight against the disease. The country's few hospitals focus mainly on basic care and trauma wounds and lack the expertise and equipment needed to deal with infectious diseases.