The Federal Communications Commission (FCC) on Thursday voted to beef up oversight of undersea submarine cables that host nearly all internet traffic, saying they will block Chinese firms from selling related products and will allow the agency to quickly greenlight approvals for tech firms headquartered in the U.S. which meet certain conditions.

In an unprecedented move, the FCC also said it plans to mandate that owners and operators of submarine line terminal equipment (SLTE) be licensed.

SLTE plays the most important role in the submarine cable system by connecting it to U.S. terrestrial facilities. The SLTE licensing requirement will ensure FCC oversight of one of the most vulnerable parts of the submarine cable networks, according to an FCC press release.

Big tech has long sought a more streamlined process and faster turnaround to lay additional cable systems that are needed as surging internet traffic and the emergence of artificial intelligence demands more infrastructure.

The new rules will exempt cable operators who can certify high security standards, have operated cables “without incident” and agree to ongoing oversight from having to undergo an intensive review for approval, according to an FCC press release. Operators exempt from the intensive review process also have to agree to not use potentially insecure foreign equipment, the agency said.

The revamped regulations will also safeguard the cables by updating protections that “address vulnerabilities related to principal equipment, third-party service providers and other areas of concern,” the press release said.

The FCC has been working to bolster the security of submarine internet cables for some time and last year blocked companies it had identified as risks to national security from supplying equipment.

Those firms were Huawei, China Telecom, ZTE and China Mobile. The new rules will go much further by also banning equipment from anywhere in China or any other country deemed a foreign adversary.

The FCC first announced it planned to bar Chinese firms from the market in July 2025.

At the time, the FCC said the ban would be one element of a suite of policies meant to fuel the expansion of submarine telecommunications infrastructure while beefing up firewalls to guard against “foreign adversary threats.”

“We have seen submarine cable infrastructure threatened in recent years by foreign adversaries, like China,” Chairman Brendan Carr said in a statement at the time. “We are therefore taking action here to guard our submarine cables against foreign adversary ownership, and access as well as cyber and physical threats.”

Spying is the biggest threat posed by China’s involvement in the undersea cable business, officials have said. The U.S. government is still grappling with the Salt Typhoon hacks which continue to be a problem more than a year after they first came to light in late 2024.

Taiwan also has said that China threatens its undersea cables. In the Baltic Sea region, bad actors have physically damaged cables several times.

“Undersea cables are the unsung heroes of the global internet — carrying up to 99% of global internet traffic,” FCC Chair Brandon Carr said in a Thursday statement. 

Carr said that building cables faster will make the internet more reliable and faster, especially given that AI is placing huge demands on connectivity. But his focus is on better protecting the highly vulnerable system, he said.

“Submarine cables face greater threats than ever: Bad actors seek access to the sensitive data and communications that run on these cables, and threats from cyber or physical disruptions only grow,” the statement said.

In April, the British government revealed that it had discovered what it called a secret Russia submarine operation encircling cables and pipelines in the ocean near the northern half of the U.K.

A Russian attack submarine and other vessels were involved in what the UK Ministry of Defence called “nefarious activity over critical undersea infrastructure elsewhere.”

After realizing that the UK had spotted its vessels, the Russians withdrew, officials have said.