World Athletics said it had taken the decision alongside organisers "with regret" as a result of the global health situation.

Competition was due to take place in Nanjing between March 19 and 21 next year.

This was already a delay of a year as the event was initially the 2020 Championships and due to run from March 13 to 15.

Action at the Cube gymnasium at the Nanjing Youth Olympic Sports Park is now set for 2023 as Serbian capital Belgrade has already been named as the host of the 2022 World Athletics Indoor Championships.

The flagship indoor event was one of the first major sports competitions to be moved because of the COVID-19 crisis, which originated in China, when World Athletics announced the original delay at the end of January.

The fact that it has been postponed again nearly a year on starkly represents just how serious the impact of the pandemic has been on global sport.

"It is with regret that we have agreed with the organisers of the World Athletics Indoor Championships in Nanjing to postpone the event to March 2023," World Athletics said.

"Whilst we have been liaising with the Organising Committee and the Chinese Athletics Association to evaluate the staging over the last few weeks, given the current global situation, there is still significant uncertainty about the state of the COVID-19 pandemic in the early part of 2021.

"For the safety of our athletes and technical officials, we must duly consider the risks in bringing a large group of people to attend the event under the pandemic situation and fully respect and carry out the pandemic prevention policy of the host country.

"The indoor season for athletics falls within a narrow calendar window (up to the end of March) so it is not possible to extend the event to later in the year.

"We would like Nanjing to be the host of our World Indoor Championships given the extensive planning and preparation they have put into this event so have agreed they will stage the event one year after the World Indoor Championships in Belgrade in 2022.

"Despite this postponement, our athletes will still have substantial competitive opportunities available in the early part of 2021 through the World Indoor Tour which comprises 26 meetings spread across 12 countries in Europe and North America. 

"The World Indoor Tour runs from the end of January to the end of February 2021 and is organised across three different tiers of competition - gold, silver and bronze."