The FAA lifted a nationwide ground stop on Friday after a communications failure at air traffic control centers caused chaos at ​US airports and triggered the longest shutdown since the September 11, 2001, attacks.

Transportation Secretary Sean Duffy said US airspace reopened at 8:15 p.m. Eastern Time (0115 GMT), ‌but warned that departures would resume gradually and it would take time for airlines to restore normal operations, Reuters reported.

“It’s going to be slow,” Duffy told reporters at the White House.

More than 6,600 flights were canceled and 8,600 delayed, with another 1,500 already canceled for Sunday, according to FlightRadar24. Aviation analysts said the four-hour nationwide grounding could disrupt airline schedules for days.

Duffy said tens of thousands of passengers were stranded at airports around the country. Duffy said he ​and Homeland Security Secretary Markwayne Mullin had met with President Donald Trump in the Oval Office to discuss the outage.

The failure is the latest and most dramatic sign of ​strain on a US air traffic control system beset by aging technology, equipment and communications problems and a shortage of several thousand controllers.

Duffy said the ⁠trouble began at 3:36 p.m., when air traffic control centers experienced instability in radar and communications systems.

“Our switches, our routers actually got overloaded with data and they started to give us inconsistencies ​in the data from those routers and because of that we shut the system down,” Duffy said, adding that at no stage did they completely lose radar or communications and they were able to safely land thousands ​of planes.

Duffy said the immediate problem had been fixed and that flying was safe, but warned that a broader overhaul of the aging air traffic control system was needed to prevent similar failures.

$50 BILLION AVIATION OVERHAUL

Duffy blamed Congress for failing to fund a new system that he said could prevent such outages, and called for $50 billion to modernize it.

Earlier on Friday, before the outage, the White House and Department of Transportation had urged Congress ​to approve $30.1 billion to upgrade the nation’s aging airports and air traffic control infrastructure.

“What we have is an incredibly old air traffic control system,” Duffy said.

“Give us the money to fix it.”

Homeland ​Security Secretary Mullin said there was “zero evidence” so far that the outage resulted from a cyberattack or a rogue AI system, though investigators had not ruled out either possibility.

“It appears this was mechanically driven, however, we’re still ‌looking,” Mullin said.

The ⁠National Security Agency was working with the Department of Homeland Security on the investigation, he added.

The outage appeared to be affecting a telecommunications network overseen by L3Harris Technologies, according to two airline officials. The network handles critical radio frequencies used by air traffic controllers to communicate with pilots. L3Harris did not respond to a request for comment.

PAIN NOT OVER FOR PASSENGERS

Though the ground stop was lifted, the disruption for passengers was far from over. From Boston to Seattle and New York to Los Angeles, passengers crowded departure halls and airline desks as delays and cancellations mounted and aircraft ​remained parked at gates.

Thousands of passengers faced being ​stranded overnight. Edward Kargbo, 50, from West Chester, ⁠Pennsylvania, had been scheduled to take a 9 p.m. Ethiopian Airlines flight to Lomé, Togo. Instead, he planned to spend the night at the airport before a rescheduled flight at 6 a.m. on Saturday.

“I have to squat the night here,” he said. “I’m stranded.”

Louise Maher, 47, was also caught up ​in the disruption at Newark after her British Airways flight to London was caught up in the aviation meltdown.

“I might cry at some ​point but not yet,” she ⁠said.

US airlines will not be required to provide compensation to stranded passengers because the carriers were not responsible for the FAA system failures.

The only other nationwide ground stop since the September 11 attacks came in January 2023, when the FAA halted domestic departures for about 90 minutes.

Investors were already pricing in a financial hit to airlines. Shares of American Airlines (AAL.O), opens new tab, United Airlines (UAL.O), opens new tab and Delta Air Lines fell between 1% and ⁠2% in after-hours ​trading, while JetBlue Airways dropped about 3%.

American Airlines said it was prioritizing flights to smaller cities outside its major ​hubs and international destinations to position aircraft and crews for a faster recovery.

Secretary ​of State Marco Rubio attacked the International Criminal Court in a speech to a conservative legal group on ‌Friday, arguing for a muscular foreign policy and against international law restraining US actions.

Rubio’s speech to the Federalist Society in Washington, his first prepared remarks since Republicans were routed in the midterm elections on November 3, heightens speculation over whether he will leave his roles as national security adviser ​and top US diplomat to run for president in 2028, Reuters reported.

Rubio, who has at times sought to provide an intellectual justification ​for President Donald Trump’s “America First” foreign policy, has firmly denied reports he will soon embark on a ⁠presidential campaign, but the Federalist Society is an occasional stop for Republican hopefuls.

He has dismissed criticisms that the Trump administration has ​broken international law by such actions as seizing Venezuelan then-President Nicolas Maduro and striking boats in the Caribbean and Eastern Pacific that ​it says were carrying drugs.

In his speech, Rubio said the goal of the US-Israeli war against Iran was to prevent Tehran from ever developing a nuclear weapon, which he said was particularly urgent because the Islamic Republic’s “radical Shia clerics” had an “expansionist mentality.”

He contrasted this with the government of North Korea’s ​Kim Jong Un, whom Trump has met three times. “I’m not excusing the terrible things that have happened there,” Rubio said of ​North Korea. “I’m just saying he (Kim) is not expansionist. He’s not trying to invade Japan or, you know, China or whatever.”

The US, Rubio said, would ‌not “submit to ⁠the sterile vision of radical judges or soulless global bureaucrats,” repeating his assertion that the court would try to prosecute US officials or service members that he used to justify sanctions against the ICC announced last month.

“Americans have never agreed to submit to the ICC’s authority, but that court and its allies in the global bureaucracy have appointed themselves judge and jury and executioner of the ​international order,” Rubio said.

The Trump ​administration has long been hostile ⁠to the Netherlands-based court, founded in 2002 to prosecute war crimes, crimes against humanity and genocide, and has previously imposed sanctions on its prosecutors and judges. The ICC has received strong backing ​from most member states, which include all EU countries and all members of the NATO alliance ​apart from the ⁠United States and Turkey.

Washington has denounced the court over arrest warrants issued for Israeli officials including Prime Minister Benjamin Netanyahu, and an investigation into actions of US soldiers in Afghanistan, which the ICC says is “deprioritized.”

The US sanctions, designed to stifle the ICC’s ability to operate, ⁠will take ​effect in April unless supporters of the Netherlands-based court can reach an ​agreement with the US to avert them.

Rubio suggested that if the court tried to enforce its rulings against Americans, Washington would respond with force. Quoting the Roman ​general Pompey, Rubio said the US response would be: “Stop quoting laws to men with swords.”

Russian President Vladimir Putin has agreed to include European representatives in the next round of Ukraine peace talks, a US envoy said, while Ukrainian President Volodymyr Zelenskiy welcomed the prospect, calling it an important step towards advancing diplomatic efforts.

US special envoy Steve Witkoff announced the development following his meeting with Putin at the Kremlin on Thursday. He said European participation was important, as the countries were partners in efforts to resolve the conflict.

Witkoff and fellow US envoy Jared Kushner later travelled to Ireland, where they met with Zelenskiy on the sidelines of a European summit in Dublin.

The Ukrainian president welcomed the prospect of European involvement and expressed hope that the next round of negotiations would focus on de-escalation and possible ceasefire arrangements.

Zelenskiy said it was important to remove obstacles to the negotiations and establish an agenda that could help reduce tensions and move the conflict towards a peaceful resolution.

However, Putin stressed that Moscow had never opposed dialogue with European countries, claiming that European governments had been responsible for ending direct engagement with Russia.

The Russian president also warned that deploying Western troops in Ukraine under a potential peace agreement would be considered a security threat by Moscow and could lead to a resumption of hostilities.

Putin urged Washington to work with its European allies to determine whether they genuinely wanted peace or continued conflict in Ukraine.

Meanwhile, Kremlin aide Yuri Ushakov did not confirm European participation in the next round of talks and criticised the current European position on the conflict, describing it as a path towards an endless war.

The latest developments follow two days of trilateral negotiations between Russian, Ukrainian and US representatives in Abu Dhabi, marking the first direct US-mediated talks between Moscow and Kyiv in nine months.

Both sides reported some progress but acknowledged that major disagreements remain, particularly over territorial issues. Russia currently controls about one-fifth of Ukraine, while Kyiv continues to reject surrendering the remaining parts of the eastern Donbas region.

Separately, Zelenskiy raised concerns over restrictions affecting Starshield satellite communications, saying the disruptions had affected the entire front line. The Ukrainian president warned that limitations on the US-made system could have significant implications for Ukraine’s military operations.

The developments highlight continued diplomatic efforts to end the war, although major differences between Russia, Ukraine and their Western partners remain unresolved.