The 29-year-old from the Philippines claimed silver in the under-53 kilogram division at the Rio 2016 Olympic Games. 

She had been aiming to upgrade her medal at Tokyo 2020, but the Games are currently in doubt due to the outbreak of coronavirus. 

"There are things we can’t control and we can’t do anything – the effects of coronavirus are something unimaginable," said Diaz on Facebook.

"Panic, fear and frustration is controlling us right now.

"As an athlete we don’t stop when we fail once, even twice.

"The most important thing is we do our best and, at the end of the day, we won’t regret anything.

"I will remain focused and determined to improve every single day together with #TeamHD who prepared me and sacrificed a lot to represent God and Philippines well in the Olympics."

Diaz had been due to depart for Cali in Colombia for the South American Championships, her final qualifying competition for Tokyo 2020.

This was postponed however, with Colombia enforcing a travel ban for visitors due to coronavirus.

The International Weightlifting Federation Executive Board met recently to discuss changes to the qualifying system necessitated by the postponement or cancellation of several important competitions.

Cases of coronavirus have now exceeded 216,000, with more than 8,000 deaths. 

Despite the ongoing crisis, the International Olympic Committee (IOC) has claimed there is no need for "any drastic decisions at this stage" regarding Tokyo 2020. 

Many have recently questioned this stance, with Spanish Olympic Committee President Alejandro Blanco urging the IOC to postpone the Games because his athletes are currently unable to train. 

IOC member Hayley Wickenheiser says insisting the Olympics will go ahead as planned is "irresponsible" and Olympic pole vault champion Katerina Stefanidi of Greece has accused the IOC of leaving athletes "at risk".

The Olympics are due to open on July 24. 

There are 889 confirmed cases of coronavirus in Japan, with 29 deaths.