In what has been dubbed a "rip and replace" initiative, The Federal Communications Commission estimated that the costs would be $4.98 billion,$1.9 billion more than Congress previously anticipated.

Departing FCC Chair Jessica Rosenworcel warned Congress of the $3.08 billion shortfall, insisting it's "putting both our national security and the connectivity of rural consumers who depend on these networks at risk."

Rosenworcel - who will leave the role on January 20, 2025 - also warned it would put the 911 service at risk in some rural areas.

It comes as a federal appeals court ruled that Chinese-owned TikTok could be banned in the US if Byte Dance doesn't find An American buyer by January 19, 2025.

President-elect Donald Trump previously threatened to have the video-sharing platform banned amid spying concerns, despite the firm insisting it would never share any of its data with the Chinese government.