North Korea in April announced it would not attend the delayed Tokyo 2020 Olympics, citing concerns over the COVID-19 pandemic.

The Olympic Committee of the Democratic People's Republic of Korea in the reclusive country did not officially inform the IOC of its decision, made during its General Assembly.

"The problem was they did not inform us officially," said IOC director of Olympic Solidarity and NOC relations James McLeod. 

"We had a lot of ongoing discussions on reasons and to offer them as many assurances as possible."

The IOC said after its latest Executive Board meeting today that quota places earned by North Korea would go to the athletes who are next in line in each sport.

At least 10 Olympic berths are set to be redistributed.

"We would like 206 National Olympic Committees to take part in the Games," Macleod said. 

"It got to the point where we had to make a decision on the reallocation of the qualified places because we didn’t want to jeopardise those places for other athletes that were waiting for that."

North Korea's participation at Tokyo 2020 had been set to be used as a chance for dialogue with South Korea and other countries, including Japan and the United States.

Pyongyang's relations with the west have been tense in recent years, particularly due to its nuclear programme and missile launches.

Tokyo 2020 host Japan's dealings with North Korea are particularly strained, with Pyongyang accused of abducting dozens of Japanese citizens in the 1970s and 1980s.

In 2017, Kim Jong-un fired missiles over Japan and another launch into the sea last month again raised fears about the country's weapons expansion.

North Korea's decision to withdraw came less than a week after South Korean capital Seoul announced it had submitted a joint bid with the North for the 2032 Games to the IOC.

The IOC is set to award the 2032 Games to Brisbane after installing the Australian bid as its preferred candidate.

In 1988, North Korea boycotted the Summer Olympics in the South's capital Seoul, but they were welcomed with open arms when their neighbour hosted the 2018 Winter Games in Pyeongchang.

A unified team took part in the women's ice hockey tournament and the two countries marched together at the Opening and Closing Ceremonies under a joint flag.