North Korea fired what appeared to be two short-range ballistic missiles off its east coast on Saturday, the latest in a series of such launches by Pyongyang as the world struggles with the coronavirus pandemic.

The South Korean military condemned the launches as "extremely inappropriate given the difficult situation the world is experiencing due to COVID-19... We urge them to stop immediately."

North Korea has not reported any cases of the coronavirus, which has turned into a major crisis with 11,300 deaths and more than 270,000 infections worldwide.

There has been widespread speculation, however, that the virus has reached the isolated nation, and health experts have warned that it could devastate the country given its weak medical infrastructure and widespread malnutrition.

Japan's defence ministry also confirmed the North Korean launches.

For decades, North Korea's leadership has faced international criticism for prioritising spending on its military and nuclear weapons programme instead of providing for the population -- even during times of famine.

Pyongyang considers its military development necessary for security in the face of what it describes as American aggression. North Korea is under multiple sets of punishing sanctions over its nuclear and missile programmes.

Hopes for a thaw after meetings between North Korean leader Kim Jong Un and US President Donald Trump were dented as they failed to produce any substantial progress on denuclearising the Korean peninsula, and Pyongyang has since continued to refine its military capabilities, analysts say.

With the latest launch Pyongyang "continues an international strategy of trying to normalise its missile tests", Leif-Eric Easley, a professor at Ewha University in Seoul, told AFP.

- 'Draconian restrictions' - 

Shortly before the launch, North Korea's official news agency KCNA reported that the rubber-stamp parliament, the Supreme People's Assembly, would convene on April 10.

The event would involve gathering nearly 700 officials in one place, analysts said. Such events have been banned in many parts of the world to curb the spread of the coronavirus.

"North Korea would not risk holding such a large-scale national political event if the regime was not confident about preventing or containing the spread of the virus," Rachel Minyoung Lee, a senior analyst at specialist website NK News, told AFP.

Earlier this month, Kim Jong Un sent a letter to South Korean President Moon Jae-in, offering "comfort" as Seoul battled what was the worst outbreak of the virus outside China at the time.

South Korea has since largely brought the outbreak under control.

Despite North Korea insisting it does not have a single case of COVID-19, Pyongyang's "draconian restrictions on movement, mask-wearing propaganda, public punishment of 'corrupt' elites violating quarantine efforts, and rush to build medical facilities suggest COVID-19 has penetrated the country," Ewha University's Easley said.

"Pyongyang is likely struggling with a coronavirus crisis on a national scale."

With fears swirling about a COVID-19 outbreak in North Korea, the UN's special rapporteur on human rights Tomas Ojea Quintana earlier this month called for Pyongyang to provide access to outside medical experts and humanitarian assistance.

The UN Security Council said last month that it would make humanitarian exemptions to sanctions on North Korea to help it fight the coronavirus.