U.S. House lawmakers have formally requested that the CEOs of Microsoft, Alphabet, Meta, and Amazon clarify the safeguards they have in place to protect undersea submarine cables from threats posed by China and Russia. The lawmakers are specifically seeking disclosure on whether Chinese firms such as Huawei Marine, China Telecom, or China Unicom are involved in maintaining or servicing submarine cable systems that include U.S. ownership stakes. The inquiry comes amid growing national security concerns regarding the vulnerability of submarine communications infrastructure. Three Republican House members have led the effort, emphasizing the risks associated with Chinese involvement in these critical systems. The lawmakers have asked the tech companies to explain the measures they have adopted to address these security challenges.