Afghan President Ashraf Ghani has tested negative for the coronavirus, an official said Tuesday, days after news leaked out of an outbreak among his staff.

"The President is healthy and is leading government efforts on all fronts. All precautions are in place to make sure his work environment is safe and healthy," Ghani's spokesman Sediq Sediqqi said on Twitter.

Ghani and his wife were both tested and "both results are negative," he added.

About 20 workers in Kabul's presidential palace and a dozen more in an adjoining office had contracted the virus, officials told AFP on Saturday. Recent official photos had shown 70-year-old Ghani wearing a mask and gloves, and mainly holding online meetings with officials.

But on Tuesday a healthy-looking Ghani appeared on TV and urged Afghans to take the virus seriously. "Coronavirus took all by surprise," he said. "But we, from the first days, took this virus seriously and by the grace of God the number of fatalities in our country is lower than in other countries," he said.

Neighbouring Pakistan's Prime Minister Imran Khan will also be tested for COVID-19, his doctor announced. The test comes after Faisal Edhi, the owner and operator of Pakistan's largest private charity, said he had tested positive for the highly contagious disease. He met with Khan last week in Islamabad.

Pakistan and Afghanistan, where handshakes and close family gatherings are the norm, have both struggled to persuade citizens to practice social distancing. So far, Pakistan has confirmed at least 192 deaths from coronavirus and Afghanistan 36, but many believe the low numbers are because of limited access to testing.