United Airlines today announced it will increase service to China from two to four weekly flights between San Francisco and Shanghai's Pudong International Airport via Seoul's Incheon International Airport.

Beginning September 4, United said it will operate four weekly flights with Boeing 777-300ER aircraft from San Francisco to Shanghai on Wednesdays, Fridays, Saturdays and Sundays.

Customers travelling from Shanghai will return to San Francisco on Mondays, Thursdays, Saturdays and Sundays.

"United has served mainland China for more than three decades and we look forward to continuing to connect customers travelling between the US and Shanghai with two additional flights beginning in September," said Patrick Quayle, United's vice president of International Network and Alliances.

In July, United began operating twice-weekly service between San Francisco and Shanghai via Seoul.

It is the largest US carrier serving China prior to suspending service in February due to COVID-19. In 2019, United operated five daily flights between Shanghai and its hubs in San Francisco, Los Angeles, Chicago and New York/Newark.

United said it is committed to putting health and safety at the forefront of every customer's journey, with the goal of delivering an industry-leading standard of cleanliness through its United CleanPlus program. United has also teamed up with Clorox and Cleveland Clinic to redefine cleaning and health safety procedures from check-in to landing.