(Bloomberg) -- The U.S. Navy has reached an agreement with General Dynamics Corp. on a multibillion-dollar deal to buy the next batch of Virginia-class attack submarines, according to the service.

After protracted negotiations, the deal was cut from 11 submarines to 9 because funding was running more than $1 billion short, with an option to buy a 10th vessel in 2023, according to service documents and congressional correspondence. The value of the resulting agreement wasn’t immediately disclosed.

“We have reached a multiyear” agreement “and are working to announce a contract” by Dec. 31, Commander Danny Hernandez, a Navy spokesman, said in a statement. It “will achieve significant savings, will include important lethality enhancements,” and “provide critical stability to the industrial base. Further information will be available upon contract award,” he said.

Elizabeth Power, a spokeswoman with General Dynamics’ Electric Boat unit, which makes the Virginia class sub with Huntington Ingalls Industries Inc., said “we have been working closely with the Navy and stand ready to support their needs. The contract being contemplated allows us to maintain a stable Virginia-class build rate.”

To contact the reporter on this story: Tony Capaccio in Washington at acapaccio@bloomberg.net

To contact the editors responsible for this story: Bill Faries at wfaries@bloomberg.net, Larry Liebert

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