• Japan is experiencing a sharp increase in COVID-19 cases.
• The surge has prompted protests to postpone the Tokyo Olympics. 
• The US State Department just advised citizens not to travel to Japan. 
• See more stories on Insider’s business page.

The US State Department is warning Americans to not travel to Japan because of a rise in COVID-19 cases.

Coming just ahead of the Olympics, the department issued a “Level 4: Do Not Travel” advisory on Monday, the highest warning against travel. 

There have been mounting calls inside Japan to postpone the Olympics amid the country’s coronavirus outbreak. 

An online petition to cancel the Olympics, which went live last Wednesday, has so far garnered more than 388,000 signatures.

Billionaire SoftBank founder Masayoshi Son also joined the calls to postpone the event. 

“Currently more than 80% of people want the Olympics to be postponed or canceled. Who and on what authority is it being forced through?” Son wrote on Twitter in Japanese on Saturday. 

A state of emergency in Tokyo has been extended until the end of May to combat the spread of the virus as only 3.5% of the population has been vaccinated so far. 

Japan has recorded more than 722,600 coronavirus cases, with over 12,300 deaths, according to data from Johns Hopkins University.