Outgoing U.K. Prime Minister Keir Starmer on June 30 revealed an additional 15 billion pound (approximately $19.8 billion) investment over four years to bring defense spending to 80 billion pounds by 2029 in a much-delayed and highly anticipated Defence Investment Plan (DIP), The Guardian reported. Among other things, the DIP provides major investments in the Global Combat Air Programme with Japan and Italy to develop a new stealth fighter jet, to strengthen the United Kingdom's nuclear deterrent via new funding for submarines, nuclear-capable fighters and a new warhead, and to acquire and integrate autonomous technologies for the different military services.

The DIP, which details how the government will allocate its defense spending, was expected to be released last fall but was repeatedly delayed due to significant budgetary disagreements between the United Kingdom's finance and defense ministries. The DIP follows the Strategic Defense Review, released in June 2025, which laid out the U.K. government's overall defense strategy.