The US Supreme Court has blocked President Joe Biden's COVID-19 vaccination-or-testing mandate for large businesses, with the conservative justices deeming the policy an improper imposition on the lives and health of many Americans.
The court did, however, endorse a separate federal vaccine requirement for healthcare facilities.
Mr Biden voiced disappointment with the conservative-majority court's decision to halt his administration's rule requiring vaccines or weekly COVID-19 tests for employees at businesses with at least 100 employees.
Mr Biden said it was up to states and employers to decide whether to require workers "to take the simple and effective step of getting vaccinated".
The court was divided in both cases, centring on pandemic-related federal regulations at a time of escalating coronavirus infections driven by the Omicron variant in a nation that leads the world with more than 845,000 COVID-19 deaths.
It ruled 6-3 to block the rule involving large businesses — a policy that applied to more than 80 million employees.
The court's majority downplayed the risk COVID-19 specifically posed in the workplace, comparing it instead to "day-to-day" crime and pollution hazards that individuals face everywhere.
The court said it was not an ordinary use of federal power, but instead "a significant encroachment on the lives — and health — of a vast number of employees."
The vote was 5-4 to allow the healthcare worker rule, which requires vaccination for about 10.3 million workers at 76,000 healthcare facilities including hospitals and nursing homes that accept money from the Medicare and Medicaid government health insurance programs for elderly, disabled and low-income Americans.
In a statement, Mr Biden said the court's decision allowing the healthcare worker mandate "will save lives" and his administration would enforce it.
Workers must be vaccinated by the end of February.
The court said the rule affecting large businesses, issued by the Occupational Safety and Health Administration (OSHA),
"Permitting OSHA to regulate the hazards of daily life — simply because most Americans have jobs and face those same risks while on the clock — would significantly expand OSHA's regulatory authority without clear congressional authorisation," the court added.
Biden doubles US free test pledge
As the Omicron variant continues to spread, Mr Biden said on Thursday the US government would procure an additional 500 million COVID-19 tests to help meet demand across the country.
The order comes on top of another 500 million tests that the White House pledged before the Christmas holiday would be available to Americans this month.
The President has come under criticism for not focusing more on testing earlier as part of his strategy for fighting the pandemic.
A nationwide shortage of tests has plagued the response in recent weeks during the rampant spread of the highly contagious Omicron variant.
A White House official said earlier on Thursday the tests would be free for American consumers and that the White House would share more details about their distribution at a later date.
Tests have been difficult for many Americans to find, driven in part by rapid test supply shortages as well as staffing shortages at the urgent care centres, pop-up sites and pharmacies that administer the tests.
More recently, staffing at the laboratories that process the more complex PCR tests has also become a factor, frustrating many seeking to know quickly whether they are infected with COVID-19.
Mr Biden acknowledged Americans' frustration but said testing availability had improved.
"That's a huge leap."
Biden said the administration was on track to roll out a website next week from which people would be able to order free tests to be shipped to their homes.
He also said the administration would announce next week how it would make masks available to Americans for free.
ABC/wires
