WASHINGTON (Reuters) - The Federal Communications Commission (FCC) said on Tuesday it has resolved two investigations into the America Movil Submarine Cable System that connects the United States to Colombia and Costa Rica.

The commission said the undersea cable connections were made without the approval of the commission or a U.S. government committee known as "Team Telecom," which had prevented a required national security concern review.

The FCC said the two companies responsible, LATAM Telecommunications and Puerto Rico Telephone Company, will each pay a $1 million civil penalty, after they admitted to the violations and agreed to enter into a compliance plan.

The U.S. government in recent years has been scrutinizing undersea cable connections, especially involving China. Around 300 undersea cables form the backbone of the internet, carrying 99% of the world's data traffic.

Puerto Rico Telephone Company, which does business as Claro Puerto Rico, declined to comment. LATAM Telecommunications did not immediately respond to a request for comment.

"Undersea cables keep us globally connected and are essential part of the digital economy. But they can pose real security risks if the FCC and its national security partners aren't properly given the chance to review where new cables may be installed," said FCC Chairwoman Jessica Rosenworcel.

The FCC said construction began on a cable landing station in Isla San Andres, Colombia, in March 2020, that became operational in September 2021. A cable landing station in Puerto Limon, Costa Rica, began operation in November 2022, with both connecting to the America Movil Submarine Cable System, but neither company sought FCC authorization until 2023, it added.

The FCC had granted Puerto Rico Telephone and LATAM in 2013 authorization for the America Movil undersea high-capacity fiber-optic cable system connecting the United States to Central and South America but it had not authorized the latest connections. The FCC did not accuse America Movil of any wrongdoing.

The FCC said the penalties were much larger than prior actions on undersea cables "reflecting the increased emphasis on data security issues in the national security sphere."