(CNN) President Joe Biden aimed to reassure vaccinated Americans that they can still proceed with their holiday plans without fear of becoming seriously ill, announcing a number of new efforts to combat a surge of Covid-19 cases in the United States.
"I know some Americans are wondering if you can safely celebrate the holidays with your family and friends. The answer is, yes you can if you and those you celebrate with are vaccinated, particularly if you've gotten your booster shot," Biden said in a White House speech Tuesday.
The speech, which came just days before Christmas, reflects Biden's renewed focus on the coronavirus pandemic as anxiety rises around the country at the steep spike in cases and concerns about whether new restrictive measures will be needed to limit the spread.
Biden emphasized repeatedly throughout the speech that the current moment is different than March 2020, when the coronavirus solidified its grip on the US.
"The other question folks are asking is, 'Are we going back to March 2020?' ... The answer is absolutely no. No," Biden said.
The President told vaccinated Americans they should feel comfortable celebrating the holidays as they planned if they take the proper precautions, but he also warned the tens of millions of Americans who have so far declined to get shots that they run a high risk of becoming ill or hospitalized. And he also invoked the name of his predecessor to encourage Americans to get their booster shot.
"I got my booster shot as soon as they were available," the President said, "and just the other day former President Trump announced he had gotten his booster shot."
"It may be one of the few things he and I agree on," Biden added. "People with booster shots are highly protected. Join them, join us."
During his speech, Biden announced the purchase of a half-billion at-home rapid Covid-19 tests, one of a series of new steps he unveiled as the country faces a potentially crippling wintertime surge of infections.
The 500 million new tests will be made available next month and will reach Americans through the mail, according to the White House.
"To be clear, we're not sending a test to every single home in the country," White House press secretary Jen Psaki said during Tuesday's White House press briefing. "We are providing an opportunity, another opportunity or ability for people to ... go on a website and request a test if their preference is to get that test to their home. Not everybody will do that. But we want people who want to do that, who want to get tested, who want to request test that way to have that ability to do (it)."
The President told reporters after his speech that the current shortage of Covid-19 tests in the US is "not a failure," but rather a reflection of a dramatic surge in cases.
"No it's not," he said, "because Covid is spreading so rapidly."
"The alarms are going off," the President said, adding, "I don't think anybody anticipated this would be as rapid at spreading as it did ... then all of the sudden it was like everybody rushed to the counter was a big, big rush."
"I knew that was coming," Biden insisted, "so what I tried to do was meet with the companies to use the Defense Production Act to get a half a billion more tests."
Asked by another reporter what took so long to ramp up production of tests, Biden seemed irritated at the question.
"Come on, 'What took so long?'" he asked. "What took so long is it didn't take long at all."
The administration is still working to determine how many tests each household may request. Senior administration officials were unable to provide any new details about exactly when the website to request the tests will launch and how quickly tests will be shipped out. Psaki said Tuesday that the expectation is that the website will be able to sustain a surge of incoming web traffic.
And a senior administration official said during a briefing with CNN Tuesday morning that the administration is still "working through all the details. And we'll have those in the coming weeks."
The official said the "first deliveries" of those tests will happen in January and that the website will launch "in January or around January as well." The official also said the White House is "working through all the details" when asked how Americans without internet access could secure tests.
The new test shipment scheme came during remarks meant to underscore the White House's plan to confront what is expected to be a large spike in cases driven by the now-dominant Omicron variant in the coming weeks. Already, cases are rising rapidly in areas around the country and hospitals are nearing capacity.
Lines for testing centers have stretched for blocks in certain areas, including the northeast, leading the White House to develop plans to open new federal testing sites in New York City before Christmas.
Distributing free at-home tests to all Americans was written off by the White House as recently as this month. Press secretary Jen Psaki scoffed earlier this month when asked if tests should be free and given out, available everywhere.
"Should we just send one to every American?" she asked.
But on Tuesday in the briefing room, Psaki expressed some regret about her earlier comments.
"There's not a day that goes by that I don't leave this podium and wish I would have said something with greater context or a more precision or additional information," Psaki said.
"There was a lot of good questioning on testing, and during that briefing, I conveyed a lot of information about our expansion of testing, about the 15 million tests that we were making available about the 20,000 free testing sites," she continued. "Should I have included that additional context?... Yes, going back I wish I would have done that."
Among the President's new initiatives is a plan to prepare 1,000 military service members to deploy to overburdened hospitals across the country in January and February, administration officials said. Those service members will include doctors, nurses, medics and other military medical personnel.
An official said, "God willing" the full 1,000 wouldn't be needed, "but if we do, they are ready and they're mobilized."
Biden also announced new vaccination sites and increased vaccine access, and will deploy hundreds of additional federal vaccinators.
Though demand for vaccines has dwindled in recent months, the surge caused by the Delta variant earlier this year did lead to increased demand for vaccinations in some of the hardest hit areas.
Biden also addressed FEMA efforts to expand hospital capacity and to pre-position medical supplies in places where stocks may run low in the coming weeks.
In his remarks, the President acknowledged a likely rise in cases -- including among vaccinated people -- but emphasized the drastically different outcomes for those with shots and those unprotected by vaccines.
Biden and his team have been adamant that federal lockdown recommendations aren't in the cards this time. And in his remarks, Biden focused on steps primarily to forestall a crippling of the US public health system than on efforts to fully stop the spread of the virus.
The White House plan announced Tuesday does not ship tests to every American; instead people would request the tests online instead. Those who utilize them will not have to report their results to public health agencies, officials said.
Pressed on that shift, a senior administration official insisted that the new plan "builds" on the administration's previous testing initiatives and pointed to increased supply.
The official also pointed out that "demand for tests ... has spiked now" amid the Omicron surge and the holiday season and said that the government's purchase of 500 million tests is an extra layer on top of existing commercial supply.
The administration had already announced a plan requiring health insurance providers to reimburse plan-holders for the cost of at-home tests; that initiative remains in place next year.
This story has been updated with additional details.