Only the WTA Finals in Shenzhen in China will remain on the calendar from the two countries and the status of the competition is still under discussion.

In 2019, China held the Shenzhen Open, the Zhengzhou Open, the Jiangxi Open, the Guangzhou Open, the Wuhan Open, the China Open and the Tianjin Open, as well as the WTA Elite Trophy and the WTA Finals.

Japan staged the Japan Women's Open and the Pan Pacific Open in the same year.

Tournaments could be relocated to later this year to allow more opportunities after the delayed Olympic Games in Tokyo, which ends on August 8.

"We are disappointed that our world-class events in China and Japan will not take place this year," said WTA chairman and chief executive Steve Simon.

"We are working on a parallel path to provide playing opportunities in other regions, one being our return to the BNP Paribas Open in Indian Wells as we look forward to this two-week event in October.

"We would like to acknowledge the dedication and significant efforts made by our affected tournaments in exploring all possibilities to stage the events this year and their continued commitment to the WTA.

"We very much look forward to returning in 2022."

The WTA Chicago Women's Open has been added to the 2021 calendar and is scheduled for the week of August 23.

It is a new tournament at the WTA 250 level.

Japan continues to have a high rate of daily COVID-19 cases with just three weeks until the Tokyo 2020 Olympics start on July 23.

Yesterday there were 1,819 cases and 41 deaths from COVID-19 confirmed in Japan.

So far there have been more than 799,000 cases of COVID-19 in Japan, resulting in the deaths of at least 14,800 people.

China continues to implement strict COVID-19 travel restrictions which has led to the cancellation of several sporting competitions, including test events for the Beijing 2022 Winter Olympics.