Nearly every other country has reported coronavirus cases, with the World Health Organization saying on Wednesday that there were nearly one million confirmed infections globally.
Aside from China, South Korea endured one of the worst early outbreaks of the virus, which has claimed more than 45,000 lives around the world.
Experts have said the North is particularly vulnerable to the virus because of its weak medical system, and defectors have accused Pyongyang of covering up an outbreak.
The top US military commander in South Korea, General Robert Abrams, said last month he was "fairly certain" the North had confirmed cases of the virus.
US president Donald Trump also said North Korea "is going through something" and offered "cooperation in the anti-epidemic work", in a personal letter to North Korean leader Kim Jong Un.
Pyongyang -- which is subject to multiple international sanctions over its nuclear and ballistic missile programmes -- has sought virus-related aid.
In February, Russia's foreign ministry said it provided Pyongyang with 1,500 coronavirus diagnostic test kits at its request "due to the persisting risk of the new COVID-19".
The United Nations has granted sanctions exemptions to relief groups including Doctors without Borders and UNICEF on items such as diagnostic kits, face masks, protective equipment and disinfectants.
It was not immediately clear whether those supplies had been transferred to the North, and neither organisation responded to inquiries by AFP.
The World Health Organisation plans to spend $900,000 to support Pyongyang's coronavirus response activities, according to data posted on the UN Office for the Coordination of Humanitarian Affairs website.