The U.S. Food and Drug Administration is speeding up its timetable for full approval of the Pfizer coronavirus vaccine, hoping to complete the process by early September.

President Joe Biden said last week that he expected a fully approved vaccine in early fall, but the unofficial FDA deadline is Labor Day or sooner, according to multiple people familiar with the plan, The New York Times reported. The agency said in a statement that its leaders recognized that full approval might counter vaccine hesitancy and had "taken an all-hands-on-deck approach" to completing full approval.

The move could help boost vaccination rates at a moment when the highly transmissible delta variant is driving up the number of new cases across the country. A number of universities and hospitals, the Defense Department, and at least one major city, San Francisco, are expected to mandate vaccines once one is fully approved. Final approval could help clarify legal issues about mandates, The Timesreported.

Moderna, the second most widely used vaccine in the United States, filed for final approval of its vaccine on June 1. But the company is still submitting data and has not said when it will finish, The Times reported. Johnson & Johnson, the third vaccine authorized for emergency use, has not yet applied for full approval but plans to do so later this year.

At the same time, senior officials at the FDA and other agencies are debating whether at least some people who are already vaccinated will need booster shots. Senior administration officials increasingly believe that vulnerable populations like those with compromised immune systems and older people will need them, The Times reported. A decision to fully approve the Pfizer vaccine will give doctors more freedom to prescribe additional shots for certain Americans, including those with weakened immune systems.