March 31 (Reuters) - AT&T has reached a deal to invest about $1 billion to improve the Commerce Department's FirstNet and deliver $1 billion in cost savings for the program via reduced rates, a U.S government agency said on Tuesday.

The telecommunications company was awarded the 25-year contract to build the federal emergency cellular network FirstNet in 2017, years after a federal commission recommended setting up such a system following the 9/11 attacks.

The system, which helps first responders such as medical personnel, firefighters and police officers communicate vital information on a single network, is used by 31,000 U.S. agencies.

The agreement was made possible through U.S. President Donald Trump's executive order in early 2025, asking federal agencies to review all contracts, the National Telecommunications and Information Administration said in a statement.

"This agreement-in-principle... reflects AT&T's ongoing dedication to our public-private partnership," AT&T's President of Public Sector Wes Anderson said.