Major airlines across the world rushed Wednesday to cancel flights heading to the US or change the planes they are using because of safety concerns over the new 5G deployment.

Emirates, Air India, All Nippon Airways, Japan Airlines, Lufthansa and British Airways all announced that they have canceled or rerouted flights into the US. Some airlines said they were warned that the Boeing 777, a plane used by carriers worldwide, was particularly affected by the high-speed wireless standard.

The US Federal Aviation Administration (FAA) has cleared several aircraft to fly into airports with 5G signals, but the Boeing 777 isn't on the list.

The airline industry is concerned because high-speed 5G internet uses C-band frequencies close to some types of radio altimeter used by aircraft to measure their altitude and could interfere with that equipment, which is particularly critical when landing in bad weather.

AT&T and Verizon agreed to delay their rollout of 5G twice before — in December and again in early January — to try to work out a compromise with the airline industry, the FAA and other stakeholders.

Dubai-based Emirates, the world's largest operator of Boeing 777s, has taken one of the biggest hits. The company said it would halt flights to Boston, Chicago, Dallas-Fort Worth; Houston, Miami, Newark, New Jersey; Orlando, Florida; San Francisco and Seattle over the issue. It said it would continue flights to Los Angeles, New York and Washington.

"We are working closely with aircraft manufacturers and the relevant authorities to alleviate operational concerns, and we hope to resume our US services as soon as possible," Emirates said in a statement.

Air India said it would suspend service to San Francisco, Chicago, Newark and New York "due to the deployment of the 5G communications" equipment. It will continue to fly into Washington Dulles.

Japan's two major airlines, All Nippon Airways and Japan Airlines, said they canceled some flights to the United States scheduled to use Boeing 777 aircraft, but will operate some flights using Boeing 787s instead.

Germany's Lufthansa canceled a flight from Frankfurt to Miami. The company said it was switching aircraft used on some US services from the Boeing 747-8 to the 747-400. Its subsidiary Austrian Airlines said it would switch from a 777 to a 767 on its Newark service.

Delta Airlines said it is planning for the possibility of weather-related cancellations as early as Wednesday due to the new 5G service in the vicinity of dozens of US airports.

The cancellations and changes came a day after AT&T and Verizon said they would delay activating 5G on some towers around key US airports.

The FCC in 2020 set a spectrum buffer between the 5G band and altimeter spectrum to resolve safety concerns. But the FAA said last month that possible interference from new 5G transmitters could still prevent some pilots from using the instruments.

The FAA in December also issued an urgent order forbidding pilots from using the potentially affected altimeters around airports where low-visibility conditions would otherwise require them.

Dozens of other countries have deployed similar mobile networks, sometimes with concessions such as reducing the power of the networks near airports, as France has done, The Associated Press reported. But in the US, the issue has pitted the FAA and the airlines against the Federal Communications Commission and the telecom companies.

China completed the deployment of its first 5G-covered airport at Guangzhou Baiyun International Airport in January 2019, according to Xinhua News.

"We are frustrated by the FAA's inability to do what nearly 40 countries have done, which is to safely deploy 5G technology without disrupting aviation services, and we urge it do so in a timely manner," Megan Ketterer, a spokesperson for AT&T, said Tuesday.

In a letter Tuesday, CEOs from 10 airlines told the Biden administration to push back the already-delayed rollout. Airlines estimate 1,000 flight disruptions per day because of possible interference with radar altimeters, CNN reported.

The telecom industry hasn't commented on the letter but has said fears are unfounded because there have not been problems in other countries where 5G is already deployed.