WASHINGTON — The U.S. Navy awarded a $76.6 billion contract to General Dynamics Electric Boat and HII for 14 new submarines, the largest submarine deal in the nation's history, the Navy said.

The award covers nine Block VI Virginia-class attack submarines and five Columbia-class ballistic missile submarines. Of the total, $29.5 billion is designated for the five Columbia-class vessels. The contract also incorporates $5 billion in previously allocated funds for shipyard improvements.

The contracts were finalized after a nearly three-year delay that raised concerns about the pace of naval modernization and the Navy's ability to maintain its numerical and technological edge.

General Dynamics Electric Boat is headquartered in Groton, Connecticut. HII is based in Newport News, Virginia. Both shipbuilders employ thousands of specialized workers at facilities central to national defense.

The Virginia-class attack submarines are designed for anti-submarine warfare, intelligence gathering, surveillance, reconnaissance and special forces support. The Block VI designation reflects specific technological upgrades built into the new vessels.

The Columbia-class submarines are the Navy's top shipbuilding priority, serving as the future sea-based leg of the nuclear triad. They will replace the aging Ohio-class fleet.

The contract sustains thousands of skilled manufacturing jobs and supports a supply chain spanning more than 40 states. The Navy structured the awards as incentive contract modifications intended to drive cost efficiency from both builders through design and construction.