WASHINGTON (NewsNation Now) — President Joe Biden announced Thursday federal workers will need to “attest” to being vaccinated or wear masks, regardless of COVID-19 community spread where they live.

The unvaccinated employees will also need to comply with weekly or twice weekly testing, and could face travel restrictions. The mandate applies to all federal contractors as well.

It does not apply to the military, though Biden says he’s working with the Department of Defense to add COVID-19 to the required vaccines list.

It becomes the nation’s largest vaccine mandate, affecting millions of workers. The federal government is the largest employer in the country. The U.S. has about 2.18 million civilian employees and 570,000 others work for the U.S. Postal Service, according to 2020 data.

Biden is also calling on all state and local governments to offer $100 to people who get vaccinated going forward, and the Treasury is also offering to help states that participate. Some states have offered lotteries for thousands of dollars, but only a handful have tried direct payments to everyone who rolls up their sleeve.

The president is pointing to anecdotal evidence that a $100 reward will get results. The White House says the Kroger grocery store chain tried it and saw vaccination rates jump to 75% from 50% among employees. New Mexico, Ohio and Colorado have also experimented with the idea.

Biden says states and localities can use money from his COVID relief law to pay for the incentive programs.

While cases are rising nationwide, Biden said his advisors are not expecting a “comparable” rise in hospitalization and deaths across the country. The president credited vaccinations with blunting the worst of the latest COVID-19 surge.

The president also thanked Senate Republican Leader Mitch McConnell and conservative media for encouraging vaccination. Some have argued vaccination is an individual right and the government should not be forcing citizens to make a particular medical choice.

“With freedom comes responsibility,” Biden said in a counterargument.

On Monday, the Department of Veterans Affairs became the first federal agency to require vaccinations, for its health workers. And on Tuesday, the Centers for Disease Control and Prevention reversed its masking guidelines and said that all Americans living in areas with substantial or high coronavirus transmission rates should wear masks indoors, regardless of their vaccination status.

Biden defended what critics on both sides of the aisle have called a confusing update after the president said in May the vaccine was the ticket to shedding masks permanently.

“That was true at the time because I thought there were people that were going to understand that getting vaccinated made a gigantic difference,” Biden said in a back-and-forth with a reporter after his speech. “What happened was a new variant came along, they didn’t get vaccinated, it was spread more rapidly, and more people are getting sick. That’s the difference.”

The response to the CDC’s recent guidance has been lukewarm regardless of vaccination status. Biden said in his remarks people in counties with largely vaccinated populations may never fall under the CDC’s new recommendation to put masks back on.

“The fact is if you had high vaccination rates we wouldn’t be in this spot right now,” Biden said.

He reiterated that he doesn’t anticipate any currently known COVID-19 variant causing enough of a surge to require a 2020-style lockdown because vaccines remain effective.

About 60% of American adults have been fully vaccinated. Biden missed his goal of having 70% of adults get at least one shot by July 4. The latest figure is 69.3%.

The Associated Press and Reuters contributed to this report.