Yang Xiaoming, Chairman of CNBG, delivers a speech during a government-organised visit to the production line of COVID-19 vaccine by Beijing Institute of Biological Products of Sinopharm's China National Biotec Group (CNBG), in Beijing, China February 26, 2021. REUTERS/Tingshu Wang

Liu Jingzhen, Chairman of Sinopharm, delivers a speech during a government-organised visit to the production line of COVID-19 vaccine by Beijing Institute of Biological Products of Sinopharm's China National Biotec Group (CNBG), in Beijing, China February 26, 2021. REUTERS/Tingshu Wang

A Chinese national flag flutters among Sinopharm's and China National Biotec Group (CNBG) flags, during a government-organised visit to the production line of COVID-19 vaccine by Beijing Institute of Biological Products of Sinopharm's CNBG, in Beijing, China February 26, 2021. REUTERS/Tingshu Wang

A security guard walks in front of the building of Beijing Institute of Biological Products of Sinopharm's China National Biotec Group (CNBG), during a government-organised visit to the company’s production line of COVID-19 vaccine, in Beijing, China February 26, 2021. REUTERS/Tingshu Wang

A monitor screen shows real-time footages of a production line of COVID-19 vaccine during a government-organised visit to the Beijing Institute of Biological Products of Sinopharm's China National Biotec Group (CNBG), in Beijing, China February 26, 2021. REUTERS/Tingshu Wang

Staff members stand next to a production line of COVID-19 vaccines at a packaging workshop inside the Beijing Institute of Biological Products of Sinopharm's China National Biotec Group (CNBG), during a government-organised visit to the company in Beijing, China February 26, 2021. REUTERS/Tingshu Wang

A staff member works next to a production line of COVID-19 vaccine inside the Beijing Institute of Biological Products of Sinopharm's China National Biotec Group (CNBG), during a government-organised visit to the company in Beijing, China February 26, 2021. REUTERS/Tingshu Wang

Unqualified vaccine products are seen on a production line of COVID-19 vaccine inside the Beijing Institute of Biological Products of Sinopharm's China National Biotec Group (CNBG), during a government-organised visit to the company in Beijing, China February 26, 2021. REUTERS/Tingshu Wang

A staff member checks a pack of COVID-19 vaccines on a production line at a packaging workshop inside the Beijing Institute of Biological Products of Sinopharm's China National Biotec Group (CNBG), during a government-organised visit to the company in Beijing, China February 26, 2021. REUTERS/Tingshu Wang

COVID-19 vaccines are seen on the production line at a packaging workshop inside the Beijing Institute of Biological Products of Sinopharm's China National Biotec Group (CNBG), during a government-organised visit to the company in Beijing, China February 26, 2021. REUTERS/Tingshu Wang

Packages of COVID-19 vaccines by Beijing Institute of Biological Products of Sinopharm's China National Biotec Group (CNBG), are displayed during a government-organised visit to the vaccine’s production line in Beijing, China February 26, 2021. REUTERS/Tingshu Wang

Boxes of COVID-19 vaccines are seen at a packaging workshop inside the Beijing Institute of Biological Products of Sinopharm's China National Biotec Group (CNBG), during a government-organised visit to the company’s production line in Beijing, China February 26, 2021. REUTERS/Tingshu Wang

COVID-19 vaccines are seen on a production line inside the Beijing Institute of Biological Products of Sinopharm's China National Biotec Group (CNBG), during a government-organised visit to the company in Beijing, China February 26, 2021. REUTERS/Tingshu Wang

COVID-19 vaccines are seen on a production line inside the Beijing Institute of Biological Products of Sinopharm's China National Biotec Group (CNBG), during a government-organised visit to the company in Beijing, China February 26, 2021. REUTERS/Tingshu Wang

COVID-19 vaccines are seen on a production line at a packaging workshop inside the Beijing Institute of Biological Products of Sinopharm's China National Biotec Group (CNBG), during a government-organised visit to the company in Beijing, China February 26, 2021. REUTERS/Tingshu Wang

COVID-19 vaccines are seen on a production line inside the Beijing Institute of Biological Products of Sinopharm's China National Biotec Group (CNBG), during a government-organised visit to the company in Beijing, China February 26, 2021. REUTERS/Tingshu Wang

COVID-19 vaccines are seen on a production line inside the Beijing Institute of Biological Products of Sinopharm's China National Biotec Group (CNBG), during a government-organised visit to the company in Beijing, China February 26, 2021. REUTERS/Tingshu Wang

A logo of Sinopharm is pictured during a government-organised visit to the production line of COVID-19 vaccine by Beijing Institute of Biological Products of Sinopharm's China National Biotec Group (CNBG), in Beijing, China February 26, 2021. REUTERS/Tingshu Wang

People queue up at a community vaccination centre to receive a dose of the Sinovac Biotech coronavirus disease (COVID-19) vaccine, in Hong Kong, China, February 26, 2021. REUTERS/Tyrone Siu

People queue up at a community vaccination centre to receive a dose of the Sinovac Biotech coronavirus disease (COVID-19) vaccine, in Hong Kong, China, February 26, 2021. REUTERS/Tyrone Siu

People queue up at a community vaccination centre to receive a dose of the Sinovac Biotech coronavirus disease (COVID-19) vaccine, in Hong Kong, China, February 26, 2021. REUTERS/Tyrone Siu

People wait to receive a dose of the Sinovac Biotech coronavirus disease (COVID-19) vaccine at a community vaccination centre in Hong Kong, China, February 26, 2021. REUTERS/Tyrone Siu

People queue up at a community vaccination centre to receive a dose of the Sinovac Biotech coronavirus disease (COVID-19) vaccine, in Hong Kong, China, February 26, 2021. REUTERS/Tyrone Siu

People queue up at a community vaccination centre to receive a dose of the Sinovac Biotech coronavirus disease (COVID-19) vaccine, in Hong Kong, China, February 26, 2021. REUTERS/Tyrone Siu

Chinese Commerce Minister Wang Wentao attends a State Council Information Office news conference in Beijing, China February 24, 2021. REUTERS/Carlos Garcia Rawlins

Chinese Commerce Minister Wang Wentao attends a State Council Information Office news conference in Beijing, China February 24, 2021. REUTERS/Carlos Garcia Rawlins

Chinese Commerce Minister Wang Wentao attends a State Council Information Office news conference in Beijing, China February 24, 2021. REUTERS/Carlos Garcia Rawlins

Chinese Commerce Minister Wang Wentao attends a State Council Information Office news conference in Beijing, China February 24, 2021. REUTERS/Carlos Garcia Rawlins

Chinese Commerce Minister Wang Wentao speaks during a State Council Information Office news conference in Beijing, China February 24, 2021. REUTERS/Carlos Garcia Rawlins

State Council Information Office spokesman Chen Wenjun, Chinese Commerce Minister Wang Wentao, Vice Commerce Minister Wang Shouwen and Vice Commerce Minister Qian Keming attend a State Council Information Office news conference in Beijing, China February 24, 2021. REUTERS/Carlos Garcia Rawlins

Chinese Commerce Minister Wang Wentao speaks during a State Council Information Office news conference in Beijing, China February 24, 2021. REUTERS/Carlos Garcia Rawlins

Chinese Commerce Minister Wang Wentao speaks during a State Council Information Office news conference in Beijing, China February 24, 2021. REUTERS/Carlos Garcia Rawlins

Chinese Commerce Minister Wang Wentao speaks during a State Council Information Office news conference in Beijing, China February 24, 2021. REUTERS/Carlos Garcia Rawlins

Chinese Commerce Minister Wang Wentao and Vice Commerce Minister Wang Shouwen attend a State Council Information Office news conference in Beijing, China February 24, 2021. REUTERS/Carlos Garcia Rawlins

Chinese Commerce Minister Wang Wentao speaks during a State Council Information Office news conference in Beijing, China February 24, 2021. REUTERS/Carlos Garcia Rawlins

Chinese Commerce Minister Wang Wentao speaks during a State Council Information Office news conference in Beijing, China February 24, 2021. REUTERS/Carlos Garcia Rawlins

Chinese Commerce Minister Wang Wentao attends a State Council Information Office news conference in Beijing, China February 24, 2021. REUTERS/Carlos Garcia Rawlins

Chinese Commerce Minister Wang Wentao speaks during a State Council Information Office news conference in Beijing, China February 24, 2021. REUTERS/Carlos Garcia Rawlins

Chinese Commerce Minister Wang Wentao attends a State Council Information Office news conference in Beijing, China February 24, 2021. REUTERS/Carlos Garcia Rawlins

State Council Information Office spokesman Chen Wenjun, Chinese Commerce Minister Wang Wentao, Vice Commerce Minister Wang Shouwen and Vice Commerce Minister Qian Keming attend a State Council Information Office news conference in Beijing, China February 24, 2021. REUTERS/Carlos Garcia Rawlins

Hong Kong's Finance Secretary Paul Chan (2nd L) poses for pictures at a news conference on the annual budget, in Hong Kong, China February 24, 2021. REUTERS/Yoyo Chow

Chinese Commerce Minister Wang Wentao attends a State Council Information Office news conference in Beijing, China February 24, 2021. REUTERS/Carlos Garcia Rawlins

Chinese Commerce Minister Wang Wentao speaks during a State Council Information Office news conference in Beijing, China February 24, 2021. REUTERS/Carlos Garcia Rawlins

Chinese Commerce Minister Wang Wentao speaks during a State Council Information Office news conference in Beijing, China February 24, 2021. REUTERS/Carlos Garcia Rawlins

Hong Kong's Finance Secretary Paul Chan delivers the annual budget address at the Legislative Council in Hong Kong, China February 24, 2021. REUTERS/Yoyo Chow

Protesters take part in a demonstration demanding benefits for the unemployed and a cash handout ahead of the annual budget announcement, outside the Hong Kong Government office in Hong Kong, China February 24, 2021. REUTERS/Pak Yiu

Members of the Hong Kong Fire Services Department receive a dose of the Sinovac Biotech's COVID-19 vaccine at a community vaccination center in Hong Kong, China, February 23, 2021. Paul Yeung/Pool via REUTERS

A person receives a dose of the Sinovac Biotech's COVID-19 vaccine at a community vaccination center in Hong Kong, China, February 23, 2021. Paul Yeung/Pool via REUTERS

A person receives a dose of the Sinovac Biotech's COVID-19 vaccine at a community vaccination center in Hong Kong, China, February 23, 2021. Paul Yeung/Pool via REUTERS

Officers of Hong Kong Police Force wait in line to receive a dose of the Sinovac Biotech's COVID-19 vaccine at a community vaccination center in Hong Kong, China, February 23, 2021. Paul Yeung/Pool via REUTERS

People receive a dose of the Sinovac Biotech's COVID-19 vaccine at a community vaccination center in Hong Kong, China, February 23, 2021. Paul Yeung/Pool via REUTERS

Chris Tang, commissioner of the Hong Kong Police Force, receives a dose of the Sinovac Biotech's COVID-19 vaccine at a community vaccination center in Hong Kong, China, February 23, 2021. Paul Yeung/Pool via REUTERS

Officers of Hong Kong Police Force wait to receive a dose of the Sinovac Biotech's COVID-19 vaccine at a community vaccination center in Hong Kong, China, February 23, 2021. Paul Yeung/Pool via REUTERS

An officer of Hong Kong Police Force receives a dose of the Sinovac Biotech's COVID-19 vaccine at a community vaccination center in Hong Kong, China, February 23, 2021. Paul Yeung/Pool via REUTERS

Officers of Hong Kong's Customs and Excise Department wait to receive a dose of the Sinovac Biotech's COVID-19 vaccine at a community vaccination center in Hong Kong, China, February 23, 2021. Paul Yeung/Pool via REUTERS

An officer of Hong Kong's Correctional Service Department holds his arm after receiving a dose of the Sinovac Biotech's COVID-19 vaccine at a community vaccination center in Hong Kong, China, February 23, 2021. Paul Yeung/Pool via REUTERS

Officers of Hong Kong's Customs and Excise Department wait to receive a dose of the Sinovac Biotech's COVID-19 vaccine at a community vaccination center in Hong Kong, China, February 23, 2021. Paul Yeung/Pool via REUTERS

Officers of Hong Kong's Immigration Department wait to receive a dose of the Sinovac Biotech's COVID-19 vaccine at a community vaccination center in Hong Kong, China, February 23, 2021. Paul Yeung/Pool via REUTERS

Chris Tang, commissioner of the Hong Kong Police Force, waits to receive a dose of the Sinovac Biotech's COVID-19 vaccine at a community vaccination center in Hong Kong, China, February 23, 2021. Paul Yeung/Pool via REUTERS

An officer of Hong Kong's Immigration Department prepares to receive a dose of the Sinovac Biotech's COVID-19 vaccine at a community vaccination center in Hong Kong, China, February 23, 2021. Paul Yeung/Pool via REUTERS