TikTok has lost an appeal against plans to ban the video-sharing app in the US.
The social media platform had argued the proposal was a breach of the US First Amendment, which protects freedom of speech.
TikTok pushed to overturn a law that could lead to its ban in a few months.
However, the petition was dismissed on Friday by the US Court of Appeals for the District of Columbia Circuit.
Its judges ruled the government’s ban was constitutional because it was designed “solely to protect that freedom from a foreign adversary nation and to limit that adversary’s ability to gather data on people in the United States”.
The law, which was signed off by US President Joe Biden in April, requires TikTok to break ties with its China-based parent company ByteDance by mid-January – or else it will be blocked in the country.
It was introduced following concern from some US politicians that the company might share user data with the Chinese government, despite repeated assurances from the firm that it would not.
Critics have also expressed fears that Chinese authorities may be able to manipulate TikTok’s algorithms, shaping what content users see and are influenced by. This claim is also denied.
TikTok and ByteDance are now set to launch another appeal to the US Supreme Court.
However, the two firms could also be thrown a lifeline by Donald Trump, who is due to be sworn in as president on 20 January.
Despite trying to introduce his own TikTok ban during his first term as president, the Republican has since changed his mind.
He said during the 2024 presidential campaign that he wanted to “save” the app and expressed concern that a ban would help its rival Facebook.
Mr Trump also signed up to TikTok and currently has more than 14 million followers on the site, although he has not posted anything since his election victory.
Reacting to Friday’s court ruling, a TikTok statement said: “The Supreme Court has an established historical record of protecting Americans’ right to free speech, and we expect they will do just that on this important constitutional issue.
“Unfortunately, the TikTok ban was conceived and pushed through based upon inaccurate, flawed and hypothetical information, resulting in outright censorship of the American people.”
It added: “The TikTok ban, unless stopped, will silence the voices of over 170 million Americans here in the US and around the world on 19 January 2025.”
Some 13 US states and Washington DC also launched legal action against the social media platform in October, alleging it was harming children’s mental health and was not doing enough to protect them.
TikTok dismissed the claims as “inaccurate and misleading”.
Donald Trump says that when he takes power next month he will direct the US Justice Department to “vigorously pursue” the death penalty.
The US president-elect, 78, said he would do so to protect Americans from what he called “violent rapists, murderers and monsters”.
Mr Trump was responding to President Joe Biden’s decision to commute the sentences of almost all federal inmates on death row – whom Mr Trump called “37 of the worst killers in our country”.
“When you hear the acts of each, you won’t believe that he did this. Makes no sense,” Mr Trump posted on his social media platform Truth Social.
“Relatives and friends are further devastated. They can’t believe this is happening!”
He continued: “As soon as I am inaugurated, I will direct the Justice Department to vigorously pursue the death penalty to protect American families and children from violent rapists, murderers, and monsters.
“We will be a Nation of Law and Order again!”
President Biden, 82, announced on Monday that he would reduce the sentences of 37 of the 40 federal death row prisoners to life in prison without the possibility of parole, saying he was “guided by my conscience and my experience as a public defender”.
The three others the president did not spare are Robert Bowers, who fatally shot 11 people at a Pittsburgh synagogue in 2018; Dylann Roof, who gunned down nine black churchgoers in Charleston, South Carolina, in 2015; and Dzhokhar Tsarnaev, who carried out a 2013 bombing at the Boston Marathon that killed three people and injured almost 300 others.
‘I condemn these murderers’
Despite sparing the lives of 37, Mr Biden added: “Make no mistake: I condemn these murderers, grieve for the victims of their despicable acts, and ache for all the families who have suffered unimaginable and irreparable loss.”
During Mr Trump’s first term in office between 2017 and 2021, the US Justice Department put 13 federal inmates to death.
He has since said he would like to expand capital punishment to include child rapists, migrants who kill US citizens and law enforcement officers, and those convicted of drug and human trafficking.
Mr Biden, who ran for president opposing the death penalty, put federal executions on hold when he took office in January 2021.
His latest decisions come after a coalition of criminal justice advocacy groups, former prosecutors and business leaders wrote letters to the White House asking for Mr Biden to commute the sentences ahead of Mr Trump’s inauguration on 20 January.
Pope Francis also appealed to Mr Biden, who is Catholic, to reduce the sentences to imprisonment.
Unlike executive orders, clemency decisions cannot be reversed by a president’s successor, although the death penalty can be sought more aggressively in future cases.
Denmark has announced plans to boost its defence spending for Greenland with a “stronger presence in the Arctic” – a few hours after Donald Trump repeated his call for the US to buy the vast island.
Danish defence minister Troels Lund Poulsen said the package would amount to a “double-digit billion amount” in krone, or at least $1.5bn (£1.2bn).
He told the Jyllands-Posten newspaper the money would be used to buy two inspection ships, two long-range drones and two sled dog teams as well as more personnel for Denmark’s Arctic Command in the capital Nuuk.
Denmark will also upgrade the Kangerlussuaq Airport so that it can handle F-35 fighter jets.
Greenland, which sits between the Atlantic and Arctic oceans, is 80% covered by an ice sheet and is home to a large US military base.
The world’s biggest island, whose capital is closer to New York than the Danish capital Copenhagen, has mineral, oil and natural gas wealth.
But development has been slow, leaving its economy reliant on fishing and annual subsidies from Denmark.
“For many years, we have not invested sufficiently in the Arctic, now we are planning a stronger presence,” Mr Poulsen said.
He called the timing of the announcement an “irony of fate”, coming just hours after Mr Trump’s latest comments on purchasing the territory.
With the Pituffik air base, Greenland is strategically important for the US military and its ballistic missile early-warning system.
Greenland defiant
The president-elect sparked anger on the territory when he wrote that American ownership and control of the island was an “absolute necessity” for “purposes of national security and freedom throughout the world”.
Its prime minister Mute Egede hit back, saying: “Greenland is ours. We are not for sale and will never be for sale. We must not lose our long struggle for freedom.”
And Danish defence minister Mr Poulsen said: “My response to Trump is the same as the prime minister’s. Greenland does not want to exchange the Commonwealth for other relations. But that is up to Greenland itself.”
Mr Trump also proposed buying Greenland during his first term in office – an idea the Danish Prime Minister Mette Frederiksen called “absurd”.
Greenland has been part of Denmark for more than 600 years and gained autonomy from the country in 1979.
Under Greenland’s self-government act, enacted by Denmark and Greenland in 2009, Greenlanders are recognised as a people or nation entitled to the right of self-determination, with the option of independence.
On Monday, in an announcement naming Ken Howery as his ambassador to Denmark, Mr Trump wrote: “For purposes of national security and freedom throughout the World, the United States of America feels that the ownership and control of Greenland is an absolute necessity.”
He has also threatened to take back control of the Panama Canal, accusing Panama of charging excessive rates to use the waterway, which allows ships to cross between the Pacific and Atlantic oceans.
American Airlines was forced to ground all flights in the US on Christmas Eve due to an unspecified technical issue.
The airline did not immediately say why it was stopping all flights, but social media was quickly abuzz with travellers worrying about getting to their loved ones for the holiday.
A groundstop notice was lifted not long after it was issued, but the possibility of disruption remains with so many flights needing to make up time.
Earlier on Tuesday, the airline said on social media: “An estimated timeframe has not been provided, but they’re trying to fix it in the shortest possible time.”
The Federal Aviation Agency said American Airlines was reporting “a technical issue and has requested a nationwide ground stop”.
In an update on Tuesday afternoon it said: “American Airlines reported a technical issue this morning and requested a nationwide ground stop. The ground stop has now been lifted.”
Passengers on social media reported having their flights stuck on the runway at various airports and being sent back to the gate.
American Airlines operates thousands of flights per day to more than 350 destinations in more than 60 countries.